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Introduction Biology is the science of life forms and living processes. All living organisms grow. •
Reproduction is a characteristic of living organisms
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All living organisms are made of chemicals.
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The sum total of all the chemical reactions occurring in our body is metabolism.
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Cellular organisation of the body is the defining feature of life
LIFE Living beings are called organisms. Living organisms are similar to non-living objects in being -formed of similar elements which combine in similar way to form similar molecules (called biomolecules in living organisms) and follow similar physical and chemical laws like gravitation, magnetism, action and reaction etc. Living organisms show a great biodiversity and are classified into different kingdoms-Monera, Protista, Fungi, Plantae and Animalia. All of these share the following properties •
They have definite organisation.
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They always have cellular nature so are either unicellular (e.g. Amoeba, Paramecium etc.) or multicellular (e.g., Hydra, man etc.).
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They show co-ordination between different parts of body to maintain homeostasis (constant internal environment) inside the body.
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They have the ability of movements and locomotion.
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They show metabolic functions in the presence of energy.
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These have the ability of intussusceptional (internal) growth and development.
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These have specific receptors (e.g., sense organs to receive external and internal stimuli) and specific effectors (e.g., muscles and glands to give specific response).
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These have regulatory mechanisms (e.g:, nerves and hormonal in animals, and only hormonal in plants) to maintain homeostasis inside the body.
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These show adaptations to their environment to increase their chances of survival.
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•
These show variations which help in speciation-and evolution.
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These have reproductive powers for continuity of their race.
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These have definite life span (period from birth to death).
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These undergo ageing after adulthood and then natural death.
Building blocks of life and their function: Living organism is formed of many types of inorganic as well as organic biomolecules. Inorganic compounds include water, minerals etc. and are a1ways micro-biomolecules (small sized, low molecular weight, readily soluble in water and diffusible) while organic molecules may be micro (e.g. monosugars, amino acids etc.) or macrobiomolecules (large sized, high molecular weight, insoluble or slightly soluble and non-diffusible e.g., proteins, fats, nucleic acids, etc.). These both types of biomolecules play important roles in metabolism Role of Water: Water forms 70-90% of the cellular pool It forms 65% (about two-thirds) of human body. It is formed of H and 0 in the ratio of 2:1. 95% of water is found in Free State and 5% in combined form in the cell. Water helps in sustaining the life processes. So water is called elixir or cradle of lip as life is not possible in the absence of water. Role of Oxygen: Oxygen is mainly utilized in aerobic cell respiration of the nutrients inside the mitochondria to produce energy-rich ATP molecules so is essential for life. In the absence of oxygen, only 5°/o of energy available is released. Role of Sodium chloride (common salt) : Sodium chloride plays an important role in metabolic. functions of body especially when in ionic form.
Role of Carbohydrates : Carbohydrates are organic compounds formed of C, H and 0 generally in the ratio of 1:2:1. These are commonly called saccharides (Gk. saccharon = sugar) Carbohydrates are the main storage molecules and most organisms use carbohydrates as an important fuel, breaking these bonds and releasing energy to sustain life.
Role of Proteins : Proteins are polymeric compounds formed by interlinking of amino acids (monomers) by peptide bonds. Out of about 100 types of amino acids, only 20 types of amino acids are of biological importance, so are called Magic- 20. Proteins play a vital role in the formation of structures in living organisms. Like carbohydrate and fat, protein can be broken down with the release of energy. Protein is not stored as such in the body and it is normally only used as a substantial source of energy in conditions of starvation.
Role of lipids : Lipids comprise a major group of insoluble hydrocarbons having many functions. These are polymers of alcohols (e.g. glycerol) and fatty acids interlinked by ester bonds. Complex lipids such as true fats are important organic molecules that are used to provide energy. Fats in animals also provide protection from heat loss.
Role of Nucleic Acid : These are polymers of nucleotides interlinked by phosphodiester bonds, so called polynucleotides. Each nucleotide is formed of 3 components : a pentose sugar (e.g.ribose in RNA and deoxyribose in DNA), a phosphate group and an inorganic nitrogen-base (a puriee or a pyrimidine). DNA acts as genetic material in most organisms and controls the synthesis of structural and functional proteins. RNA also act as genetic material in all plant viruses e.g. TMV and helps in protein synthesis.
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Biology________________________________________________________________________________
AXONOMY Taxis = orderly arrangement, nomos = law. Taxonomy is the study of principles and procedures of classification. This word was proposed by A.P. de. Candolle in his book ‘Theories elementaire de la botanique” (Theory of elementary botany) * Taxonomy includes study of following 4 points (1)Identification : Identification of living organisms (2)Nomenclature : Nomenclature of living organisms (3) Classification: Classification of living organisms in groups (4) Affinities: Study of inter relationship between living organisms SYSTEMATICS (Branch related with taxonomy) (A) The term “Systematics” was proposed by Linnaeus. (B) It includes description of external morphological characters of plants or living organisms. Eg. Morphological characters of Root, Stem, Leaves, Flowers (C) This description is used to know inter relationship among plants or living organisms. New systematics or Neo systematics or Biosystemafics (A) Neo - systematics A new branch- Name given by Julian F-Iuxley (1940). (B) It includes description of all the characters (internal) including morphological characters (external) of plants or living organism. Eg. Anatomical characters Cytological characters (C) It is used to know the inter relationship among living organism.
NOTE: • New systematics is mainly based oh evolutionary as well as genetic relationship (experimental taxonomy) as compared to morphological characters. • Maximum diversity is found in tropical rain forests. • Second maximum diversity is found in coral reefs. • Practical significance of taxonomy is identification of unknown organism. NOMENCLATURE • Polynomial system : According to this system name of any plant consists of many words. For eg. CaryophyllumCaryophyiium saxa tills foils gramineus umbellatis corymbis. Binomial system: 1. Binomial system was first proposed by Gaspard Bauhin in his book - ‘Pinax Theatre Botanica.” 2. Carojus Linnaeus Linnaeus used this nomenclature system for the first lime on large scale and proposed scientific name of all the plants and animals.
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* Linnaeus is the founder of binomial system. * Linnaeus proposed scientific name of plants in his book “Species plantarum”. It was published on 1 May 1753. So this was the initiation of binomial system for plants. So any name proposed (for plants) before this date is not accepted today. •
Linnaeus proposed scientific name of animals in his book “Systema nattrae’ (loth edition).
•
This 10th edition of Systema naturae was published on 1 August 1758. So initiation of binomial system for animals is believed to be started on 1 Aug.1758.
Principle of Priority The nomenclature is done by principle of priority. If two names are proposed for any plant after the 1753, the valid name is the earlier name proposed just after 1 May, 1753 ICBN - “International Code of Botanical Nomenclature’ •
ICBN - Book of rules of nomenclature
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Collection of rules regarding scientific - nomenclature of plants is known as ICBN
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ICBN was firstly proposed by Sprague, Hitchcock, Green (1930).
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ICBN was first accepted in 1961,
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12th International congress, Leningrade, revised ICBN in 1975.
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After revision it was republished in 1978. So that ICUN was published two times (1) 1961 (2) 1978
Main rules of ICBN 1. According to binomial system name of any species consists of two names (i) Generic name - Name of genus (ii) Specific name - Trival name Eg.
Solanum ↓
Generic name
tuberosum ( Potato ) ↓
Specific name
Mangfera indica
(Mango)
↓
↓
Generic name
Specific name
2. In plant nomenclature (ICBN), tautonyms are not valid i.e. generic name and specific name should not be same in plants. eg. Mangifera mangifera But tautonyms are valid (ICZN-International Nomenclature) eg, Naja naja (Indian cobra), Rattus rattus (Rat) 3. Length of generic name or specific name should not be less than 3 letters and not more than 12 letters. eg. Mangifern indica Exception Riccia pathankotensis - More than 12 letters According to ICBN this name is not valid but this name was proposed before 1961, so it is valid. 4. First letter of generic, name should be in capital letter and first letter of specific name should be in small letter. eg. Mangifera indica But if specific name is based on the name of some person, its first letter should be in capital letter. eg Isoetes Pantu
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S. When written with free hand or typed, then generic name and specific name should be separately underlined. But during printing, name should be italized. 6, Name of scientist (who proposed ndmenclatire) should be written in short after the specific name eg. Mangfera indica Lin. 7. Name of scientist should be neither underlined nor written in italics, but written in roman ,lçtters (simple alphabets) S. If any scientist has proposed wrong name then his name should be written in bracket and the scientist who corrected the name should be written after the bracket. eg. Tsuga.canadensis (Lin.) Salisbury Notes Linnaeus named this plant as Pinus canadensis 9. Scientific names should be derived from Latin or Greek languages because they are dead languages. 10. Type specimen (Herbarium Sheet) of newly discovered plant should be placed in herbarium (Dry garden). 11. Standard size of herbarium sheet is 11.5 x 16.5 inches Type specimen (herbarium sheet) are of different type Holotype: Herbarium sheet on which the first description of plant is based. Lectotype: In case of holotype is lost, second herbarium sheet prepared from the original plant is called lectotype. Neotype: in case holotype and original plant is lost then herbarium ‘sheet prepared from some Other plant of same species is called neotype. Syntype : In case holotype and original plant is lost then many herbarium sheet prepared from plants of same species is called syntype. Isotype: Duplicate of holotype - In presence of holotype a second herbarium sheet prepared from the original plant is called isotype. Paratype Additional herbarium sheet used in the first description of plant is called paratype. It is prepared from some other plant of same species having some variations. Note Nomenclature is invalid in absence of herbarium sheet. ICNB = International Code of Nomenclature for Bacteria ICVN = International Code of Viral Nomenclature ICNCP = International Code of Nomenclature for Cultivated Plants
TRINOMIAL SYSTEM Proposed by Huxley and Stricklandt According to this system name of any plant or species is composed of three names (i) Generic name (ii) Specific name (iii) Subspecific name (Name of variety) When members of any species have large variations then trinomial system is used. On the basis of dissimilarities this species is classified into sub species eg. Brassica oleracea var. botrytis (Cauliflower) Brass ica oleracea var. capitata (Cabbage) Brassica oleracea var. caulorapa (Knol-Khol) TAXONOMIC CATEGORIES
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Their are 7 main taxonomic -categories. They are obligate -categories i.e. they are strictly used at the time of any plant classification. There are some extra categories, like sub division, sub order, sub family, tribe, sub tribe,. etc. They are not regularly used. They are used only when they are needed.
Classification of Raddish:
•
Adolf Mayer - First proposed the term ‘Taxon” - for animals.
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Taxon : Plant groups or animal groups included in categories are called taxon.
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H.J. Lan: First proposed the term “Taxon” - for plants.
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The classification of any plant or animal is written in descending order.
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Hierarchy - Descending arrangement of taxonomic categories is known as hierarchy.
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Species : Smallest taxonomic category: It is basic unit of classification.
Suffix for taxa (Taxon) Division — phyta Sub div - phytina Class — opsida, phyceae, ae Order — ales Sub-order — ineae Family — aceae Sub faimly — oideae Tribe —. eae Sub tribe — mae Note: There is no suffix for Genus, Species and Kingdom.
SPECIESCONCEPT
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John Ray : Proposed the term and concept of species. To explain the species, different concepts were proposed, which are as follows (A) Biological concept of species (1) Mayer proposed the biological concept of species. (2) Mayer defined the “species” in the form of biological concept. (3) According to Mayer ‘All the members that can interbreed among themselves and can produce fertile offsprings are the members of same species” But this lefinition of Mayer was incomplete because this definition is applicable to sexually reproducing living beings because there are many organisms that have only asexual mode of reproduction. eg. Bacteria, Mycoplasma, BGA (4) The main character in determination of any species is interbreeding. But this character is not used in taxonomy. In taxonomy, the determination of species is based on other characters. eg. - Mainly morphological characters (5) In higher plants, the determination of species is maInly based on the morphology of flower (floral morphology): Because floral (reproductive) characters are more conservative as compared to veget4tive (Root, Stem, Leaf) characters i.e. they do not shows any major changes. (6) When the species is determined on the basis of interbreeding then it is called as biological species. eg. All the humans in this world can interbreed among themselves. So all the humans are the members of one biological species. (7) When the determination of species is based on other characters then it is called as taxonomic species. eg.
These 3 have same morphological characters. Therefore they belong to same taxonomic species i.e. one taxonomic species. But these three can not interbreed among themselves. Therefore on the basis of interbreeding these are three biological species. (B) Static concept of species (1) The static concept of species was proposed by Linnaeus. According to Linnaeus “species is tin- changeable” i.e. there is. no change in the character of species. The species of present day are same as they were in past and they will remains same in future. (2) Linnaeus believed in the “Theory of Special creation” Father Suarez - gave the principle of special creation. According to this theory ‘All the living organisms are created by God (Every life is created by God) and God gave the basic size and shape of all living organisms, they are still present in their actual former form. But Lamarck rejected this hypothesis. (C)Dynamic concept of species (1) It was proposed by “Lamarck” (2) According to this concept “Species is always changeable”. Changes always occur in the characters of species from one generation to next generation. And these changes are known as ‘evolution’ (D) Typological concept:
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(1) It was proposed by “Aristotle” and “Plato”. (2) According to this concept ‘There is a definite type or pattern of characters in the each species of every living organisms and all the members of species show maximum resemblance with this pattern. (Typological concept is based on single individual of species) The species in which a fixed pattern of characters is present are called as monotypic species. eg. Bacteria, blue green algee. (3) In many species, more than one type or pattern of characters are present. These are called “Polytypic species” or “Macrospecies”. eg. Brassica oleracea —, Cauliflower, Cabbage, Knol khol Polytypic Species are of three types Biotype Members of same species inhabiting similar environment and having some genetic variations are known as biotypes. Variations found in these members are permanent. These members can not interbreed among themselves. eg. Cauliflower, Cabbage, Knol-Khol are three biotypes of one species Ecotypes Members of same species inhabiting different environment and having some genetic variations are known as ecotypes. Variations are permanent. These members can interbreed among themselves but due to geographical barrier they can not interbreed. eg. Crow (Corvus splendense) found in different regions are ecotype of one species Corvus splendense splendense - Indian crow Corvus splendense insolense - Myanmar crow Corvus splendense protegatus - Srilankan crow Ecads or Ecophenes Members of same species having some non genetic variations due to environment is called Ecads. These variations are temporary eg. Every living being
This hypothesis is believed to be most acceptable. Some definition related to species 1. Linneon species: Those taxonomic species whose determination is based on morphology. They are called as linneon species. They are also called morpho-species or taxonomic species. eg. Most of species in taxonomy are linneon 2.Microspecies or Joardan’s species: Those species in which variations are very less are called Joardan’s species. They reproduce asexually so they have very less variations. 3. Sibling species or Cryptic species: Members of species which are morphologically similar but reproductively io1ated are known as sibling species i.e. they can not interbreed among themselves. Sibling species is one taxonomic species (because these members have similar morphology) but they are different biological species. [Because they can not interbreed]
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eg. Brassica oleracea Allopatric species : Those species that are found in different geographical regions and have geographical barriess between them are known as allopatric species. 4. Geographical barriess are hills, oceans, himalyan mountains. 5. Sympatric species : The species found in similar geographical regions are sympatric species. 6. Allochronic species : The species found in different time periods. eg. Man and Dinosaurs. 7. Synchronic species Those species that are found in same era, eg. Dinosaurs and Archaeoptervx. 8. Palaeo species : Those species that are extinct now and are found in the form of fossils. eg. Dinosaurs 9. Neontological species : Those species which are living presently. NOTE: Biochemical resemblances are used in the identification of Moneran species. GENUS Genus comprises a group of related species which has more characters in common in comparison to species of other genera. Example Potato, tomato and brinjal are three different species but all belong to the genus Solanum. Lion (Panthera leo), leopard (P. pardus) and tiger (P. tigris) with several common features, are all species of the genus Panthera. This genu differs from another genus Felis which includes cats.
FAMILY Family, has a group of related genera with still less number of similarities as compared to genus and species. * Families are characterised on the basis of both vegetative and reproductive features of plant species. * Example Three different genera Solanum, Petunia and Datura are placed in the family Solanaceae. Among animals for example, genus Panthera, comprising lion, tiger, leopard is put along with genus, Fells (cats) in the family Felidae. ORDER §
Order being a higher category, is the assemblage of families which exhibit a few similar characters. The similar characters are less in number as compared to different genera included in a family.
§
Plant families like Convolvulaceae, Solanaceae are included in the order Polymoniales mainly based on the floral characters.
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The animal order, Carnivora, includes families like Felidae and Cancidae.
CLASS •
This category includes related orders. Example : Order Primata comprising monkey, gorilla and gibbon is placed in class Mammalia along with order Carnivora that includes animals like tiger, cat and dog. Class Mammalia has other orders also.
PHYLUM
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• Classes comprising animals like fishes, amphibians, reptiles, birds along with mammals constitute the next higher category called Phylum. All these, based on the common features like presence of notochord and dorsal hollow neural system, are included in phylum Chordata. In case of plants, classes with a few similar characters are assigned to a higher category called Division.
KINGDOM • All animals belonging to various phyla are assigned to the highest category called Kingdom Animalia in the classification system of animals. The Kingdom Plantae, on the other hand, is distinct, and comprises all plants from various divisions.
TYPES OF TAXONOMY
1. Alpha taxonomy or classical taxonomy: It is based on external morphology, origin and evolution of plants. 2. Beta taxonomy or Explorative taxonomy: Besides externil morphology, it also includes internal characters like embryological, cytological, anatomical characters etc. 3. Omega taxonomy or Encyclopaedic taxonomy: Omega taxonomy has widest scope. It is based on all the informations or data available about plants. 4. Cytotaxonomy : The use of cytological characters of plants in classification or in solving taxonomic problems is called cytotaxonomy. Cytological characters constitute an important aid to plant taxonomy, especially in determining affinities at the generic and infrageneric levels. 5. Chemotaxonomy : The uses of chemical characters of plants in classification or in solving taxonomic problems is called chemotaxonomy or chemical taxonomy. It is based on the chemical constitution of plants. The fragrance and taste vary from species to species. The basic chemical compounds used in chemotaxonomy are alkaloids, carotenoids, tannins, polysaccharide, nucleic acids, fatty acids, amino acids, aromatic compounds etc. 6. Karyotaxonomy: Based on characters of nucleus and chromosomes. Pattern of chromosomal bands (dark bands and light bands) is most specific characters,
BRANCHES OF BOTANY
1. Anatomy- Study of internal structure 2. Phycology or Algology- Study of Algae 3. Agrostology -Study of grass 4. Anthology - Study of flowers 5. Aerobiology- Study of substances of plants, found in air. 6. Agronomy- Study of crops plants 7. Arboriculture- Study of culture of decorated plants, 8, Bio Chemistry- Study of organic substances, found in living organisms
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9. Biophysics- Study of importance in metabolic reactions of different physical theories 10. Bacteriology- Study of bacteria 11, Bryology- Study of bryophytes 12. Bio-metrics- Study related to different biotic reactions & their results. 13. Bio technology - Study of isolation of protoplasm & their culture 14. Cytology - Study of structure & functions of cell 15. Cecidology - Study of diseased knots in Plants 16. Dendrology - Study of tree 17. Dendrochronology- Study of age of trees 18. Embryology - Study of gametes formation fertilization & formation of embryo 19. Ecology - Study of inter relations between living organism & their atmosphere 20. Evolution - Study of different development process of living organism 21. Economic Botany - Study of plants of economic importance 22. Ethenobotany- Study of uses of plants by Tribals 23. Exobiology - Study of presence of possible organism on other planet 24. Euphenics - Study of control of heredity disease 25. Edaphology - Study of organism in soil 26. Floriculture - Study of culture of ornamental flowers 27. Foresty - Study of forests 28. Genetics - Study of heredity & variations 29. Gymnology - Study of Gymnosperm 30. Gerentology - Study of changes in cell with age 31. Genetic Engineering- Study of artificial genes & their transfers 32. Histology - Study of structure of tissues 33, Histochemistry- Study of different chemicals found in cells & tissues. 34. Horticulture- Study of culture of garden plant, fruits & vegetables 35. Lichenology- Study of lichens 36. Limnology - Study of fresh water plants 37.. Karyology - Study of Nucleus 38. Morphology - Study of external characters of Plants 39. Mycology - Study of fungi 40. Microbiology - Study of micro organisms 41. Mycoplasmology - Study of mycoplasma 42, Molecular Biology - Study of nucleic Acid (DNA & RNA) 43 Morphogenesis - Study of development 44. Nematology - Study of relation of plants & Nematodes 45. Olericulture - Study of culture of vegetables 46. Oncology - Study of plant cancer - -
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47. Physiology - Study of biotic activity of plants 48. Paleobotany - Study of fossil plants 49. Plant geography- Study of distribution of plants according to different geographical zones. 50. Pleriodology - Study of pteridophytes 51. Pedology - Study of soil
BOTANICAL GARDENS, HERBARIA AND RESEARCH INSTITUTE I. Oldest botanical garden is “Padua Botanical Garden” Italy (Established -1545). 2, Largest Botanical garden in the world is Royal Botanical Garden, Kew, Surrey, England, established by William Aiton, 1759. 3. Largest herbarium of the world is “Museum of Natural History’ - Paris - with a collection of 8880000 specimens. 4. Largest Botanical Garden of Asia is Indian Botanical Garden, Sibpur, Kolkota. Established by Robert Kyd, 1786. * Largest herbarium of Asia is Central National Herbarium located in Indian Botanical Garden, with a collection of 25 lakh specimens. * Indian Botanical Garden is famous due to the presence of “Great Banyan Tree’ in its campus. * In campus of Indian Botanical Garden Botanical Survey of India (BSI) is present which is established by William Rouxburgh 1890. BSI — Botanical Survey in India is done by BSI 5. National Botanical Garden, Lucknow. National Botanical Research Institute (NBRI) is located in National Botanical Garden. 6. Forest Botanical Garden, Dehradun. Forest Research Institute (FRI)is located in Forest Botanical Garden. 7. Lloyd Botanical Garden - Darjeeling. 8. CDRI - Central Drug Research Institute - Lucknow 9. CAZRI - Central Arid Zone Research Institute - Jodhpur 10. CIMAP - Central Institute of Medicinal and Aromatic Plants - Lucknow 11. IARI - Indian Agriculture Research Inst. (Pusa Inst.)- New Delhi 12. Birbal Sahni Institute of Paleobotany (National Institute of Paleobotany) - Lucknow.
CONTRIBUTIONS AND CONTRIBUTORS Contributions
Contributors
Cell theory
Schleiden and Schwann
Central Dogma of Molecular genetics (Name) Chromosomal Theory
of Linkage
Crick Morgan and Castle
Chromosomal Theory of inheritance
Sutton and Boveri
Cohesipn Theory of Ascent of Sap
Dixon and Jolly
Double fertilization of Angiosperms
Nawaschin & Guingard
Gene Theory
Morgan
(Linkage of genes)
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Germplasm Theory
Weissmann
Germ Theory of disease Induced fit
L. Pasteur
hypothesis of enzyme
Koshland
Mutation Theory
Hugo de Vries
Omnis cellula e cellula
R. Virchow
One gene one
enzyme theory
Beadle and Tatum
Operon Concept of Gene action
Jacob and Monod
Organic evolution
Darwin and Wallace
‘Protoplasm is the physical basis of life (Book) Huxley Sol gel theory of amoeba
Locomotion
Hyman,Pantin
Survival of the fittest (term)
Spencer
Telome Theory of Pteridophyta
Zimmernunn
theory of Accquired Characters
Lamarck
Theory of Natural Selection
Charles Darwin Tunica
Corpus Theory
Schmidt
INVENTIONS AND DISCOVERIES Inventions and discoveries
Contributors
Blood groups A, B and O
K. Landsteiner
ATP
Lohmann (1929)
Blood group AB
de Castello and Sturli
C3 pathway of plants
Malvin Calvin
C4 pathway of plants
Hatch and Slack
First test tube baby
Edwards and Steptoe
First vaccination
Edward Jenner
Heterothallism in fungi
Blakeslee
Insecticidal properties Of DDT
Muller (1939)
Jumping genes (transposons)
Mc Clintock
Pataiis syndrome
K.Patau
Penicillin
A. Aeming (1920)
Photophosphorylation in chloroplast
Arnon
TMV virus (discovery)
Iwanowski
Vitamin
Funk (1911)
CONNECTING AND MISSING LINKS OF BIOLOGICAL WORLD Link
Between the groups
Actinomycetes
Bacteria and Fungi
Archaeopteryx
Birds and Reptiles
Balanogiossus
Chordates and nonchordates
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Chimaera (rat or rabbit fish)
Bony and Cartilaginousfishes
Club moss
Bryophytes and Pteridophytes
Cycas
Pteridophytes and Gymnosperms
Gneriurn
Gymnosperms and Angiosperms
Neopilina
Annelida and Mollusca
Ornithorhynchus
Reptiles and Mammals
(Duck billed Platypus) Peripa ins (Walking worm)
Annelida and Arthropoda
Protopterus (Lungfish)
Pisces and Amphibia
Rickettsia
Virus and Bacteria
Virus
Living and non-living
Muscles Number
639
Smallest
Stapedius
Largest Gluteus
maximus
Longest
Sartorius
Number of cranial nerves
12 pairs
Number of spinal nerves
31 pairs
Smallest cranial nerve
Abducens
Smallest bone
Stapes
Smallest endocrine gland
Pituitary
Speed of Sneezing
60-100 miles/hour
Spinal cord weight
35gm.
Length
42-45 cm.
Organisms with their Taxonoinic Categories.
1. Most acceptable concept of species is — (1)Static concept (2) Biological concept (3)Typological concept (4) Genetic concept 2. Artificial system of classification classifies plants on the basis of — (1) One or two characters (4) None of the above
(2) Phylogenetic trends
(3) Many naturally existing
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3. The term new systematics was introduced by (1) Linnaeus (2) Bentham
(3) Hutchinson (4) Huxley
4.Group of organisms that closely resemble each interbreed in nature,other and freely constitute a— (1) Species(2) Genus
(3) Family (4) Taxon
5. ICBN was first revised in (1) 1961
(2)1964
(3) 1975
(4) 1733
6.The term taxon refers to — (1) Name of a species
(2) Name of genus
(3) Name of family
(4) A taxonomic group of any rank
7.The herbarium specimen on whose basis a new species is described for the first time is called as (1) Syntype (2) Holotype
(3) Paratype(4) Neotype
8.The scientific naming of plants began with publication of Linnaeus book — (1) Genera plantarum (2) Systema nahirae
(3) Species plantarum (4) Charaka sanhita
9. Which book most impressed the opinion of taxonomists — (1) Enquiry into plants (2) Origin of life (3) Genera plantarum (4) Origin of species 10.The basic unit of classification is — (1) Genus (2) Species
(3) Order (4) All of the above
11. Suffix for sub species is — (1) Phytina
(2) Oideae
(3) Ineae
(4) None
12.Individuals of same species having non-genetic differences due to environment are called — (1) Biotypes
(2) Ecotype
(3) Ecophenes (4) None
13.Morphologically similar but reproductively isolated species are called — (1) Neontological species
(2) Sibling species
(3) Allopatric species
(4) Morpho-species
14.Plant nomenclature means (1) To give names to plants without any rules
(2)Nomenclature of plants under the international rules
(3)Nomenclature of plants in local language
(4) Nomenclature of plants in english language
15.Taxonomy refers to — (1) Plant classification (3) Plant affinity
(2) Plant nomenclature (4) All the above
16. Which of the following is a correct name (1) Solanuni tuberosum (2) Solanum Tuberosum
(3) Solanum tuberosum Linn.
(4) All the above
17.Systematics deals with — (1) Classification
(3) Plant description
(2) Nomenclature
(4) Plant exploration
18.Scientific name of Mango plant is Mangfera indica(Linn.) Santapau. In the above name Santapaurefers to — (1) Variety of Mango (2) A taxonomist who proposed the present nomenclature in honour of linnaeus (3) A scientist who for the first time described Mango plant (4) A scientist who changed the name proposed by Linnaeus and proposed present name 19.Type specimen selected from the original material in case the holotype is missing, is called (1) Lectotype
(3) Syntype
(2) Neotype
(4) Para type
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20. Phylogeny refers to — (1) Natural classification
(2) Evolutionary classification (3) Evolutionary history
(4) Origin of algae
21. Static concept of species is given by (1) Linnaeus
2) Bentham
(3) Koch
(4) Mayr
22. In taxonomy the first step is (1) Identification
(2) Nomenclature
(3) Classification
(4) Affinities
(3) Suborder
(4) Sub family
23. The suffix - mae signifies the rank (1) Tribe
(2) Subtribe
24, Species living in different geographical areas are called — (1) Allochronic
(2) Allopatric
(3) Sympatric
(4) Siblings
25, A large number of unknown species of plants and animals are believed to be present in — (1) Temperate forests
(2) Antarctica
(3) Taiga
(4) Tropical forest
(3) John Ray
(4) De Candolle
26 Biological concept of species proposed by — (1) Linnaeus
(2) Mayr
27. For higher plants, flowers are chiefly used as a basis of classification, because — (I) These show a great variety in colour
(2) It can be preserved easily
(3) Reproductive parts are more conservative than vegetative parts
(4) None of these
28. Individuals of same species having genetic variation and occur in same environment are called— (I) Biotypes
(2) Ecotype
(3) Ecophenes
(4) Ecads
(3) Genus
(4) Species
29. The smallest unit of classificati on is — (1) Family
(2) Order
30. The binomial system of nomenclature was initially proposed by — (1) Magnus
(2) Bauhmn
(3) Caesalpinno
(4) Discorides
31. Biochemical resemblances are used in the identification of (I) Protistan species
(2) Moneran species
(3) Fungal species
(4) Higher plants
(3) Ernest Haeckel
(4) Darwin
32. Concept of phylogeny was proposed by — (1) John Ray
(2) Lamarck
33. A division is formed by combining several — (1) Orders
(2) Familiea
(3) Classes
(4) Tribes
34. An international code of botanical nomenclature was first proposed in the year (1) 1930
(2) 1830
(3) 1913
(4) 1813
35. For declaration of new species of higher plants,what characters are used — (1) Floral character of new species
(2) Anatomical characters of new species
(3) Physiological character of new species
(4) Character of endosperm
36.The standard size of herbarium sheets is (1) 11.5” x 16.5”
(2) 15.5” x 16.5 ’
(3) 18.5” x 10.5”
(4) 20.5” x 21.5”
37.Which statement is true — (1) Tautonyms do not occur in plants
(2) Tautonyms do not occur in animals
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(3) Tautonyms normally occur in animals and some time occur in plants (4) Tautonyms occur only in bacteria 38. Trinomial nomenclature of classification was proposed by— (1) Linneaus
(2) Huxley and Stricklandt
(3) John-Ray
(4) Theophrastus
39. Most of the botanical names are drawn from the following language — (1) German
(2) Greek
(3) Latin
(4) Spanish
40. Evolutionary classification is called — (1) Artificial system
(2) Natural system
(3) Phylogenetic system
(4) None of the above
41. Which of the following statements regarding nomenclature is correct — (1) Generic name always begins with capital letter whereas specific name with small letter (2) Scientific name should be printed in italics (3) Scientific name when typed or handwritten should be underlined (4) all the above 42. The systematic arrangement of taxa is called (1) Key
(2) Taxonomy
(3) Geneology
(4) Hierarchy
44. Number of obligatory categories in taxonomy are— (1) 7
(2) 8
(3)9
(4)5
43.Which is the most important but generally not used criteria for the identification of the speties — (1) Interbreeding
(3) Genetic material
(2) Morphology
(4)’ None
45. Herbarium is — (1)A garden where medicinal plants are grown (2)Garden where herbaceous plants are grown (3)Dry garden
(4)Cherriical to kill plants
46. The year of publication of ‘Species plantarum’ (1) 1853
(2) 1857
(3) 1753
(4) 1786
47. The biological concept of species is mainly based on— (1) Morphological features
(2) Morphology and method of reproduction
(3) Method of reproduction only
(4) Reproductive isolation
48. A duplicate of holotype is called — (1) Isotype
(2) Syntype
(3) Neotype
(4) Para type
(3) Darwin
(4) Koch
(3) Indica
(4) Tamarindus indicus
49. Term taxom given by — (1) Adolf Mayer
(2) Linnaeus
50. Which of the following is a species? (1) Tamarindus
(2) Indicus
51. Tautonyms are valid names according to — (1) ICBN
(2) Species plantarum
(3) Genera plantarum
(4) ICZN
52. Practical significance of taxonomy is — (1) Classification
(2) To understand diversity
(3) To understand evolution
(4) Identification of organisms
53. Which name is invalid? (1) Name not published in species plantarum
(2) Name proposed prior to 1961
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(3) Name which is not in latin
(4) Name for which holotype is not designated
54. Which system classifies a plant in more than one groups? (1) Practical classification
(2) Artificial classification
(3) Natural classification
(4) Phylegenetic classification
55. Author of book ‘Fla British Indica’ — (1) Father Santapau
(2) J.D. Hooker
(3) William Rouxburgh
(4) G. Bentham
(3) Topiary
(4) Tissue culture
56, The art of growing short plants is called — (1) Bonsai
(2) Horticulture
57. Science of characters and distribution of races is known as (1) Ethnology
(2) Sociology
(4) Anthropology
(3) Taxonomy
(2) Herpetology
(3) Serpentology
(4) None of these
58. The study of reptiles is (1) Ichthyology
59. The branch of study dealing with microscopic anatomy of tissues is — (1) Histology
(2) Cytology
(3) Morphology
(4) Palaeontology
60. Olericulture is the cultivation of — (1) Vegetables
(3) Crop plants
(2) Fruits
(4) Mushrooms
61. Oncology is the study of — (1) Dead cells
(2) Living cells
(3) Dividing cells
(4) Cancer cells
(3) Fossils
(4) Fishes
(2) Diseases
(4) Pollution
(2) Animals
(4) Microbes
62. Ornithology is the study of — (1) Reptiles
(2) Birds
63. Pedology is the science of — (1) Rocks
(3) Soil
64. Synecology refers to the ecological study of (1) Plants
(3) Community
65. Study of abnormal embryonic growth comes under— (1) Teratology
(3) Morphogenesis
(2) Ontogeny
(4) Parthenogenesis
66. The bacteria were first observed in the year 1675 by — (1)Robert Koch
(2)Louis Pasteur
(3)Robert Brown
(4)Antony van Leeuwenhoek
(3) Stanley
(4) Beijèrinck
(3) Robert Hooke
(4) Schleiden
(3) Stanley Miller
(4) Gregor Mendel
67. Plant virus was first crystallized by (1) Pine
(2) Bawden
68. The term cell was first coined by — (1) Robert Brown
(2) Schwann
69. Who studied blood groups in man — (1) Landsteiner
(2) Francis Galton
70. 10% law of energy transfer in food chain was given by— (1) Tansley
(3) Lindeman
(2) Stanley
(4) Weismann
71. The law of limiting factor was proposed by — (1) Blackman
(3) Hatch and Slack
(2) Leibig
(4) Arnol
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72. Who is famous in the field of palaeobotany (1) Bose J.C. -
(3) Metha K.C
(2) Birbal Sahni
(4) Maheshwari P
(2). Hill R.
(4) Ruben and Kamen
73. Photophosphorylation was discovered by (1) Arnon D.I.
(3) Calvin M.
74. Who was developed the concept of phagocytosis in immunity — (1) T.H. Huxley
(2) Strasburger
(3) Ernst Haeckel
(4) E. Metchnikoff
(3) Bayliss
(4) Harris
75. The term Hormone was coined by — (1) Starling
(2) Huxley
76. Who wrote a. memoir on the earthworm, Pheretima, to describe in morphology and anatomy (1) Baini Prasad
(2) Bahl K.N;
(3) Thillayampalam E.M.
(4) Das S.M.
77. Aquaculture does not include — (1) Pisces
(2) Prawns
(3) Silkworm
(4) Shell fishery
78. Match the names of branches of biology listed under column I with the help of study given under column II, choose the answer which gives the correct combination of the alphabets of the two columns — Column I
Column II
(Branch of biology)
(Field of study)
(A)Palynology
(p)Silkworks
(B)Oncology
(q)Pollens
(C)Phycology
(r)Cancer
(D)Sericulture
(s)Algae
(1) A=s..B=q,C=r,D=p (2) A=q,B=r,C=s,D=p (3) A=s,B=r,C=q,D=p (4) A=r,B=q,C=s,D=p 79. The branch which is associated with diagnosis, prevention and cure of mental disorders is — (2) Psychiatry
(1) Neurology
(3) Psychology
(4) Neuropsychiatry
80. Match the following by using codes (A) Vernalization
(1) Camerarius
(B) Double fertilization (2) Hofmeister (C) Pollination
(3) Lysenko
(D)Alternation of
(4) Nawaschin
Generations (1)A=1,B=2,C=4,D=3 (2)A=4,B=1,C=2,D=3 (3)A=3,B=2,C=1,D=4 (4)A=3,B=4,C=1,D=2 81. Match the branches of biology listed in column I with the areas of study listed in column II. Choose the answer which gives the correct combination of alphabets of the two columns —
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Column I
Column II
(Branches of biology)
(Area of study)
(A) Helminthology
(p) Study of insects
(B) Entomology
(q) Study of fungi
(C) Ornithology
(r) Study of algae
(D) Phycology
(s) Study of birds (t) Study of worms
(1) A=p,B=s,C=q,D=t (2) A=t,B=p,C=s,D=r (3) A=s,B=t,C=r,D=p (4) A=r,B=p,C=s,D=q Note (Q.82-Q.85) Each questions contain STATEMENT-1 (Assertion) and STATEMENT-2 (Reason). Each question has 4 choices (1), (2), (3) and (4) out of which ONLY ONE is correct (1) Statement- 1 is True, Statement-2 is True, and Statement-2 is a correct explanation for Statement 1 (2) Statement -1 is True, Statement -2 is True Statement-2 is NOT a correct explanation for Statement -1 (3) Statement - 1 is True, Statement- 2 is False (4) Statement -1 is False, Statement -2 is False 82. Statement 1 Botany deals with the study of plants and zoology deals with the study of animals. Statement 2 Biology is the study of living beings. 83. Statement 1 Study of internal structure is called anatomy. Statement 2 It is useful for phylogentic study. 84. Statement 1 The science of classifying organisms is called taxonomy. Statement 2 : Systematics and taxonomy have same meaning. 85. Statement 1 Formation of new species is called speciation. Statement- 2 The deme has a common gene pool.
HINTS & SOLUTION (5) (3) ICBN waS first revised in 1975.
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(10) (2) The basic. unit of classifications is species. (20) (3) Phylogeny refers to evolutionary history. (29) (4) The smallest unit of classification is species. (36) (1) The standard size of herbarium sheets is 11.5” x 16.5. (45) (3) Herbarium is dry garden. (56) (1) Bonsai is the art of growing of dwarf tree in a pot, produced by special method of cultivation. (57) (1) Science of characters and distribution of races is known as Ethnology. (58) (2) The study of reptiles is known as Herpetology. (59) (1) The branch of study dealing with microscopic anatomy of tissues is Histology. (60) (1) Olericulture is the cultivation of Vegetables (61) (4) Oncology is the study of Cancer cells (62) (2) Ornithology is the study of Birds (63) (3) Pedology is the science of Soil. (64) (3) Synecology refers to the ecological study of Community. (65) (1) Study of abnormal embryonic growth comes under Teratology (66) (4) The bacteria were first observed in the year 1675 by Antony van Leeuwenhoek (67) (3) Plant virus was first crystallized by Stanley (68) (3) The term cell was first coined by an English microcopist Robert Hooke in 1665. (69) (1) Landsteiner studied blood groups in man. (70) (3) 10% law of energy transfer in food chain was given by Lindeman. (71) (1) The law of limiting factor was proposed by Blackman. (72) (2) Birbal Sahni is famous in the field of palaeobotany. (73) (1) Photophosphorylation refers to ATP synthesis during light reaction of photosynthesis. It is proposed by Arnon D.I. (74) (4) Elie Metchnikoff won the 1908 Nobel prize in physiology and medicine for the concept of phagocytosis. (75) (1) The term Hormone was coined by Starling. (76) (2) Bahi K-N. wrote a memoir on the earthworm, Pheretima, to describe in morphology and anatomy. (77) (3)Aquaculture does not include Silkworm. (78) (2) Palynology - Study of spores and pollen grains Oncology - Study of cancer/tumorus Phycology Study of algae Sericulture - Rearing of silkworm (79) (2) The branch which is associated with diagnosis, prevention and cure of mental disorders is Psychiatry (80) (4) Vernalization - Lysenko Double fertilization - Nawaschin Pollination - Camerarius Alternation of Generations - Hofmeister (81) (2) Helminthology - Study of worms Entomplogy - Study of insects
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Ornithology - Study of birds Phycology - Study of algae (82) (1) Biology (Bio-living, logy-science). The study of living beings is called biology. Living beings on earth are mainly classified into two forms- plants and animals. Botany and zoology are the fundamental branches of biology. Word botany has been derived from greek word botane which means pasture or plants and zoology has been derived from word zoo- animals, logos-study. Theophrastus and Aristotle is called the father of botany and father of zoology respectively. (83) (2) Anatomy is the study of internal structure which can be observed with unaided eye after dissection. By studying anatomy of large number of organisms, it is useful for knowing phylogenetic similarity (homology) and phylogenetic dissimilarity (analogy). (84) (3) Taxonomy is the science of identification, nomenclature and classification of organisms. But taxonomy and systematics are different terms. Systematics is the branch of biology that deals with diversity of organisms at every level of classification. (85) (2) All new species develop from the pre-existing species. The phenomenon of development of a new species from pre-existing one is called speciation. A species is a collections of demes. The deme is a groups of populations with a common gene pool.
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CLASSIFICATION Biological classification : The art of identifying distinctions among organisms and placing them into groups that reflect their most significant features and relationship is called biological classification. The purpose of biological classification is to organise the vast number of known plants into categories that could be named, remembered and studied. According to “Ad’. de Candolle”, Classification is of two types (1) Empirical Classification (2) Rational Classification 1. Empirical Classification (i) In this type, the actual nature or character of plants is not considered. (ii) Plants are classified on the basis of their alphabetical order. i.e. on the basis of the name of plant. (iii) On the basis of name, plant kingdom can be classified in 26 groups. (There are 26 alphabets in English’ According to this classification, all plants having same initial alphabet, are placed in one group. For example : If the name of plants, starts from ‘A’, then it is placed in A group”. Similarly if it starts with ‘B’, then it is placed in ‘B - group”) (iv) This is not a true classification. It has only one application: “Listing of flora”. (v) If any scientist, writes the flora of a particular area then he uses empirical classification. Flora → Plants growing in a particular area. Two books in which flora of India is written: (i) Flora British Indica → By J.D. Hooker (ii) Flora Indica → By William Rouxburgh 2. Rational Classification : In this classification, plants are classified on the basis of their actual character or nature i.e. by viewing the characters. Type of rational classification (I) Practical classification : In this type of classification, plants are classified on the basis of their economic importance. In this type of classification morphology of plants is not considered. Oil yielding plants : Coconut, Walnut, Soya bean Fibre yielding plants Jute, Cotton
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Medicinal plants: Rauwolfia, Cinchona, Eucalyptus Note: In this classification, any plant can be a member of more than one group. eg. Turmeric: Multi uses plant it gives both medicines and spices. (ii) Artificial classification In this type of classification plants are classified on the basis of one or two morphological characters. i.e. over all morphology is not considered. e.g. Classification proposed by Linnaeus is Artificial. Linnaeus classified plant kingdom on the basis of only two characters (1) Stamens (2) Style On the basis of stamens and style, Linnaeus classified plant kingdom in to 24 classes (1) Monandria — Those flowers in which only 1stamen is present. (2) Diandria — 2 stamens in flower (3) Triandria — 3 stamens in flower (23) Polyandria Many stamens (24) Nonandria/Cryptogamia — No stamens
Note: Linnaeus divided flowering plants into 23 classes starting with class monandria with a single stamen (eg Canna) and plants with twenty or more stamens attached with calyx were assigned to class Icosandria. He also included all nonflowering plants such as algae, fungi, lichens, mosses and ferns in a separate class called cryptogamia or nonandria. tiii) Natural classification: In this type, plants are classified on the basis of their complete morphology. hi it the classification of whole plant is included (stem, root, Leaves, flower etc). Maximum characters are tak. in this classification.
Importance : Natural classification is believed to be the best classification, because it represents the natural similarities and dissimilarities of plants i.e. it represents the interrelationship among plants. In this classification, the plants belonging to the same group shows many similarities, while in artificial classification, the plants belonging to the same group shows only, for 2 similar characters. They have many dissimilarities. Natural classification is of two types (a)Natural formal (b) Natural phylogenetic (a) Natural formal In this classification, the phylogeny of the plant is not considered i.e. only the morphclosy of the plant is considered. (b) Natural phylogenetic hi this classification, both morphology and phylogeny are considered. In phyh4genetic classification, the plants are arranged on the basis of their evolution. Lamarck : Proposed the term Phylogeny” Ernest Haeckel :- Gave the concept of phylogeny Charles Darwin : Gave broad explanation of phylogeny in his book ORIGIN OF SPECIES”(1859) (Geneology → Sequence of evolution) Geneology of plant kingdom: Thallophyta → Bryophyta → Pteridophya → Gymnosperm → Angiosperm (Most advanced plants) (iv) Adansonian system or phenetic classification or Numerical classification Proposed by “Sokel and Sneath”. In it plants arc classified on the basis of numbers of similarities and dissimilarities. In this, importance to single character is not given, all characters have same importance. While in natural classification floral (reproductive) characters have more importance than vegetative (root, stem and leaves) characters.
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HISTORY OF TAXONOMY 1. Aristotle : Father of biology & father of zoology. 2. Theophrastus (A) Time - 370 - 285 B.C. (B) He is known as father of ancient plant taxonomy and father of botany. (C) Both Theophrastus & Aristotle are Greek political philosophers. (D) Theophrastus wrote many books on plants. Few of them are as follows (a) Historia plantarum
(b) Causes of plants
(c) Enquiry into plants
(E) Theophrastus gave names and descriptions of 480 plants in his book Historia plantarum. (F) Theophrastus proposes the first classification of plant kingdom. He classified plant kingdom in to four groups on the basis of growth habit. (a) Trees (b) Shrubs (c) Under shrubs (d) Herbs (G) It is artificial classification. (H) He proposed the term Annual, Biennial and Perennials. 3. Carolus Linnaeus : 11707 - 1778 (A) His real name was -Carl Von Lime (B) On the basis of work in latin language, he changed his name to Carolus Linnaeus. He was the Swedish scientist. (C) He is known as father of taxonomy, father of plant taxonomy and father of animal taxonomy. (D) Linnaeus gave the two kingdom system classification. He grouped plants and animals into kingdom plantae and kingdom Animalia respectively. (E) Linnaeus wrote many books. Some important books are: (1) Hortus uplandicus - First book
(2) Flora lapponica
(3) Philosophia botanica
(4) Critica botanica
(5) Systema naturae (1737)
(6) Genera planta rum
(7) Species plantarum -last book (1753) (F) In “Philosophia botanica Linnaeus gave the principles of nomenclature. (G) In “Systema naturae Linnaeus gave the scientific names of animals. lit this book he gave the detailed description of animal kingdom. •
He also gave the outline classification of plant kingdom in this book.
(H) In Genera plantarum” Linnaeus gave the detailed description of plant kingdom. •
He classified the plant kingdom into 24 classes on the basis of stamens and style.
•
This was an artificial classification.
•
The main basis of Linnaeus classification was the ‘Sex organs” Therefore this classification is also known as “Sexual classification’.
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(I) In ‘Species plantarum” he gave the scientific names of plants. IHe gave the description of 6000 plant species) 4. A.P. De Candolle: (A) He wrote the book - “Theories Elementaire de la botanique” (B) He was the first to propose the significance of vascular tissue in taxonomy. On this basis of vascular tissue he classified plants into two groups (a) Cellular plants (Non vascular plants) - This group includes Thallophyta and Bryophyta (b) Vascular plants - This group includes Pteridophyta, Gymnosperm and Angiosperms. 5. George Bentham (1800 -1884) and Joseph Dalton Hooker (1817 -1911): (A) Both Bentham and Hooker were related to Royal botanical garden. (B) Scientists working in botanical garden are known as curator. (C) They wrote the book “Genera plantarum” (1862 - 1883). In this book, Bentham and Hooker gave the biggest and natural classification of spermatophyta i.e. plants with seeds.
In Genera plantarum, there is description of 202 families, In it, basically the description of plants with seeds is present. Merits of Bentham and Hooker classification: The classification of Bentham and Hooker was natural formal. The classification of Bentham and Hooker was mainly based on the floral characters. This was very appreciable because floral characters are more stable than vegetative (root, stem, leaves) characters, It is the simplest classification. Therefore the arrangement of all plants in the botanical gardens and herbarium of the world is based on it. Although it is not the best classification but yet the arrangement of plants in botanical gardens and herbariums is based on it, because it is the simpler one. The main reason for its simplicity is that this classification is based on actual observations.
Demerits of Bentham and Hooker In this classification the phylogeny of plants is not considered, because in it, gymnosperms are placed in between dicots and monocots. The sequence of evolution is as follows Phylogeny → Gymnosperm → Dicots → Monocots 6. A. W. Eichler: •
Syllabus de vorlesungen uber phanerogamen kunde - Book written by Eichler.
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•
In this book, Eichler gave the first phylogenetic classification of plant kingdom.
•
The classification of Eichler is very little phylogenetic.
In this way Eichler classified plant kingdom into five divisions and arranged them in the order of evolution (Phylogeny) Thallophyta → Bryophyta → Pteridophyta → Gymnosperm → Angiosperm 7. Engler (1844 - 1930) & Prantl (1849 - 1893) Book - “Die Naturlichen Pflanzen Familien’ lIe gave the phylogenetic classification of plant kingdom. This classification was more phylogenetic as compared to Eichlers classification.
8. Oswald Tippo (A) Proposed the biggest phylogenetic classification of plant kingdom.
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(B) This classification is the complete classification of plant kingdom. (C) This is the most acceptable classification for books and study.
These ten divisions include three types of organisms (1) Algae - 7 - div. (2) Bacteria - 1- div. (3) Fungi - 2div.
Note Tippo does not use the word pteridophyta 9. Karl Menz: (A) He showed the importance of serology in taxonomy. (B) Similarities and dissimilarities in stru. of proteins help to know the phylogenetic relationship of living beings. Living organisms which are phylogenetically close relatives have more similarities in their proteins. Organisms which are distantly related have different proteins.
NOTE: Phylogenetic relationship of plants and animals can be established by animal serum.Serology indicates that chimpanzee is closest relative of man. 10. Haeckel (A) Haeckel gave the three kingdom (Protista, Plantae, Animalia) system of classification.
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(B) Haeckel established the kingdom Protista. (C) The term Trotista was given by C. Cuvier. (D) Haeckel grouped those living organisms in Protista which did not have tissues. Kingdom Protista Prokaryotes, Protozoa, Porifera, Algae & fungi * First tissue was originated in animal kingdom in → Coelentrata * First tissues was originated in plant kingdom in → Bryophyta
11. Copeland: He gave the four kingdom system of classification. (I) Mychota : Dougherty & Allen gave the name “Monera” to Mychota of Copeland. All the prokaryotes are grouped in Monera. (ii) Protista or Prototista Copeland grouped those eukaryotes in protista, which are visually different than normal plants and animals. e.g. Brown algae, Red algae, Fungi, Protozoa (iii)Plantae or Metaphyta : Remaining all eukaryotic plants are grouped. (iv) Animalia or Metazoa : Remaining all eukaryotic animals are grouped.
12, R.H. WHITTAKER (1969): (A) He gave the five kingdom system of classification. (B) This classification was believed to be modern The five kingdom classification of Whittaker was based on 3 main characters (a) Complexity of cell : Cell is prokaryote or Eukaryote, on this basis, kingdom Monera is formed. And all the prokaryotes are grouped in to it. (b) Complexity of organism Organism is unicellular or multicellular, on this basis kingdom Protista was formed, and all the unicellular eukaryotes are grouped into it.
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(c) Nutrition : Organism is autotrophic or heterotrophic, on this basis kingdom Mycota, Plantae and Animalia was formed. Except fungi (heterotrophic) all the plants are autotrophs. Therefore fungi is separated from plants and placed in kingdom mycota. And remaining all the autotrophic plants are placed in kingdom Plantae, Since all the animals are heterotrophs, therefore they are placed in fifth kingdom i.e. kingdom Animalia. Five Kingdom 1. Monera : All the prokaryote (Eubacteria, Actinomycetes BGA, Mycoplasma) and Akaryote (virus) 2. Protista All the Unicellular eukaryotes (Protozoans, Dinoflagellates, Diatoms, Euglenoids, Slime molds) 3. Mycota: True fungi 4. Plantae MUlticellular plants (Algae, Bryophyte, Pteridophyte, Gymnosperm, Angiosperm) 5. Animalia Multicellular animals
13. SIX KINGDOM Carl Woese suggested separate kingdom for “Archaebacteria”. He proposed six kingdom classification. Carl woese divided living beings in three domain on the basis of r -RNA gene sequencing.
KINGDOM MONERA * Bacteria are the sole members of the Kingdom Monera. •
Bacteria are grouped under four categories based
•
on their shape; the spherical Coccus, the rod- shaped Bacillus, the comma-shaped Vibrium and the spiral Spirillurn.
•
Compared to many other organisms, bacteria as a group show the most extensive metabolic diversity. Some of the bacteria are autotrophic, i.e., they synthesise their own food from inorganic substrates, They may be photosynthetic autotrophic or chemosynthetic autotrophic. The vast majority of bacteria are heterotrophs, i.e., they do not synthesise their own food but depend on other organisms or on dead organic matter for food.
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Characteristics of monera •
Monera (Monos - single) includes prokaryotes and shows the following characters
•
They are typically unicellular organisms (but one group is mycelial).
•
The genetic material is naked circular DNA, not enclosed by nuclear envelope.
•
Ribosomes and simple chromatophores are the only subcellular organelles in the cytoplasm. The ribosomes are 70 5. Mitochondria, plastids, golgi apparatus, lysosomes, endoplasmic reticulum, centrosome, etc., are lacking.
•
Sap vacuoles do not occur. Instead, gas vacuole may be present.
•
The predominant mode of nutrition is absorptive but some groups are photosynthetic (holophytic) and chemosynthetic.
•
The organisms are non-motile or move by beating of simple flagella or by gliding.
•
Flagella, if present, are composed of many intertwined chains of a protein flagellin They are not enclosed by any membrane and grow at the tip.
•
Moneran cells are microscopic (1 to few microns in length).
•
Most organisms bear a rigid cell wall (Peptidoglycan).
•
Reproduction is primarily asexual by binary fission or budding. Mitotic apparatus is not formed during cell division,
Bacteria shape Cocci: They are oval or spherical in shape. They are called micrococcus when occur singly as in Micrococcus, diplococcus when found in pairs as in Diplococcus pneuinoniae, tetracoccus in fours, streptococcus when found in chains as in Streptococcus lactis, staphylococcus when occurring in grape like clusters as in Staphylococcus aureus and Sarcine, when found in cubical packets of 8 or 64 as in Sarcina. Bacilli: They are rod—shaped bacteria with or without flagella. They may occur singly (bacillus), in pairs (diplobacillus) or in chain (streptobacillus). Vibrios : These are small and ‘comma or kidney’ like, They have a flagellum at one end and are motile, vibrio bacteria has curve in its cell e.g., Vibrio cholerae, Spirillum : They are spiral or coiled like a corkscrew. The spirillar forms are usually rigid and bear two or more flagella at one or both the ends e.g., Spirillum, Spirochaetes etc. Filament: The body of bacterium is filamentous like a fungal mycelia. The filaments are very small e.g., Beggiota, Thiothrix etc. Stalked: The body of bacterium possesses a stalk e.g., Caulobacter. Budded : The body of bacterium is swollen at places e.g., Rhodomicrobiu Structure of bacteria Capsule : In a large number of bacteria, a slimy capsule is present outside the cell wall. It is composed of polysaccharides and the nitrogenous substances (amino acids) are also present in addition. This slime layer becomes thick, called capsule.
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Biology________________________________________________________________________________
The bacteria, which form a capsule, are called capsulated or virulent bacteria. The capsule is usually found in parasitic forms e.g., Bacillus anthracis, Diplococcus pneumoniae, Mycobacterium tuberculosis. * Cell wall : All bacterial cells are covered by a strong, rigid cell wall. Therefore, they are classified under plants. Inner to the capsule cell wall is present. It is made up of polysaccharides, proteins and lipids. In the cell wall of bacteria there are two important sugar derivatives i.e., NAG and NAM (N-acetyl glucosamine and Nacetyl muramic acid) and besides L or D - alanine, D-glutamic acid and diaminopimelic acid are also found. * Plasma membrane Each bacterial cell has plasma membrane situated just internal to the cell wall. It is a thin, elastic and differentially or selectively permeable membrane. It is composed of large amounts of phospholipids. proteins and some amounts of polysaccharides but lacks sterols. It is characterised by possessing respiratory enzymes.
Cytoplasm: The cytoplasm is a complex aqueous fluid or semifluid ground substance (matrix) consisting of carbohydrates, soluble proteins, enzymes, co-enzymes, vitamins, lipids, mineral salts and nucleic acids. The organic matter is in the colloidal state. The cytoplasm is granular due to presence of a large number of ribosomes- Ribosomes in bacteria are found in the form of polyribosome. Membranous organelles such as mitochondria, endoplasmic reticulum, golgi bodies, lysosomes and vacuoles are absent, In some photosynthetic bacteria the plasma membrane gives rise to large vesicular thylakoids which are rich in bacteriochlorophylls and proteins.
Nucleoid: It is also known as genophore, naked nucleus, incipient nucleus. There is nuclear material DNA which is double helical and circular. It is surrounded by some typical protein (polyamine) but not histone proteins. Histones (basic proteins) are altogether absent in bacteria. This incipient nucleus or primitive nucleus is named as nucleoid or genophore.
Plasmid: In addition to the normal DNA chromosomes many bacteria (e.g., E.co?i) have extra chromosomal genetic elements or DNA. These elements are called plasmids. Plasmids are small circular double stranded DNA molecules. The plasmid DNA replicates independently maintaining independent identity and may carry some important genes. Plasmid terms was given by Lederberg (1952). Some plasmids re integrating into the bacterial DNA chromosome called episomes.
Flagella: These are fine, thread-like, protoplasmic appendages which extend through the cell wall arid the slime layer of the flagellated bacterial cells. These help in bacteria to swim about in the liquid medium. Bacterial flagella are the most primitive of all motile organs. Each is composed of a single thin fibril as against the 9+2 fibrillar structure of eukaryotic cells. The flagellum is composed entirely of flagellin protein. Pill or Fimbriae Besides flagella, some tiny or small hair-like outgrowths are present on bacterial cell surface. These are called pill and are made up of pilin protein. They measure about 0.5—2tm in length and 3—5iim in diameter. These are of 8 types I, II, III, IV, V, VI, VII, and F types. I to F are called sex pili. These are present in all most all gram —ve bacteria and few gram +ve bacteria. Fimbriae take part in attachment like holding the bacteria to solid surfaces. The function of pili is not in motility but they help in the attachment of the bacterial cells. Some sex pili acts as conjugation canals through which DNA of one cell passes into the other cell.
33
Biology________________________________________________________________________________
Staining of bacteria (1) Simple staining: The coloration of bacteria by applying a single solution of stain to a fixed smear is termed simple staining. The cells usually stain uniformly.
(2) Gram staining: This technique was introduced by Hans Christian Gram in 1884. It is a specific technique which is used to classify bacteria into two groups Gram +ve and Gram —ye. The bacteria are stained with weakly alkaline solution of crystal violet. The stained slide of bacteria is then treated with 0.5 percent iodine solution. This is followed by washing with water or acetone or 95% ethyl alcohol. The bacteria which retain the purple stain are called as Gram +ve. Those which become decolourised are called as Gram —ye. In general the wall of Gram +ve bacteria have simpler nature as compared to Gram —ye bacteria. E.coli is a Gram —ve bacterium. Gram negative bacterium can be seen with other stain safranin. Gram positive bacteria : e.g., Pneumococcus, Streptococcus, Staphylococcus, Bacillus, Clostridium, mycobacterium, Streptomyces. Gram negative bacteria e.g., Salmonella, Pseudomonas, Escherichia, Haemophilus, Helicobacter, Vibria, Rhizobium, Nutrition in bacteria On the basis of mode of nutrition, bacteria are grouped into two broad categories. First is autotrophic and second is heterotrophic bacteria. Autotrophic bacteria These bacteria are able to synthesize their own food from inorganic substances, as green plants do. Their carbon is derived from carbon dioxide. The hydrogen needed to reduce carbon to organic form comes from sources such as atmospheric H2, H2S or NH3. Heterotrophic bacteria : Most of the bacteria can not synthesize their own organic food. They are dependent on external organic materials and require atleast one organic compound as a source of carbon of their growth and energy. Such bacteria are called heterotrophic bacteria. Heterotrophic bacteria are of three typesParasites, Saprotrophs and Symbionts. Archaebacteria •
These bacteria are special since they live in some of the most harsh habitats such as extreme salty areas (halophiles). hot springs (thermoacidophiles) and marshy areas (methanogens).
•
Archaebacteria differ from other bacteria in having a different cell wall structure and this feature is responsible for their survival in extreme conditions.
•
Methanogens are present in the guts of several ruminant animals such as cows and buffaloes and they are responsible for the production of methane (biogas) from the dung of these animals. Eubacteria (True Bacteria)
•
There are thousands of different eubacteria or ‘true bacteria’. They are characterised by the presence of a rigid cell wall, and if motile, a flagellum.
•
The cyanobacteria (also referred to as blue-green algae) have chlorophyll a similar to green plants and are photosynthetic autotrophs.
•
The cyanobacteria are unicellular, colonial or filamentous, marine or terrestrial algae. The colonies are generally surrounded by gelatinous sheath. They often form blooms in polluted water bodies. Some of these organisms can fix atmospheric nitrogen in specialised cells called heterocysts, e.g., Nostoc and Anabaena.
34
Biology________________________________________________________________________________
Chemosynthetic autotrophic bacteria oxidise various inorganic substances such as nitrates, nitrites and ammonia and use the released energy for their ATh production. They play a great role in recycling nutrients like nitrogen, phosphorous, iron and sulphur. Heterotrophic bacteria are the most abundant in nature. The majority are important decomposers. Many of them have a significant impact on human affairs. Theyare helpful in making curd from milk, production of antibiotics, fixing nitrogen in legume roots, etc. Some are pathogens causing damage to human beings, crops, farm animals and pets. Cholera, typhoid, tetanus, citrus canker are well known diseases caused by different bacteria. Bacteria reproduce mainly by fission. Sometimes, under unfavourable conditions, they produce sporeá. They also reproduce by a sort of sexual reproduction by adopting a primitive type of DNA transfer from one bacterium to the other. The Mycoplasmas are organisms that completely lack a cell wall. They are the smallest living cells known and can survive without oxygen. Many mycoplasma are pathogenic in animals and plants. Mycoplamsa hominis causes pleuropneumonia inflammation of genitals and endocarditis, etc. Myco plasma pneumoniae causes primary a typical pneumonia (PAP), haemorrhagic laryngitis, etc. Mycoplasma fermentatus and M. hominis cause infertility in man, otitis media (inflamation of middle ear). * Mycoplasma mycoides causes pneumonia in cattle. Mycoplasma bovigenitalum, causes inflammation of genitals in animals. Mycoplamsa agalactia causes agalactia of sheep and goat. * Common mycoplasmal diseases of plants are: Bunchy top of papaya, witches’ broom of legumes, yellow dwarf of tobacco, stripe disease of sugarcane, little leaf of brinjal, clover phylloidy, big bud of tomato etc. KINGDOM PROTISTA •
All single-celled eukaryotes are placed under Protista, but the boundaries of this kingdom are not well defined.
•
Members of Protista are primarily aquatic. This kingdom forms a link with the others dealing with plants, animals and fungi. Being eukaryotes, the protistan cell body contains a well defined nucleus and other membrane-bound organeiles. Some have flagella or cilia.
35 •
Biology________________________________________________________________________________ Protists reproduce asexually and sexually by a process involving cell fusion and zygote formation. It may be photosynthetic, holotrophic, saprotrophic, parasitic and symbionts. Some have mixotrophic nutrition (holotrophic + saprobic). The photosynthetic, floating protists are collectively called phytoplankton. The free-floating, holozoic protozoans are collectively termed zooplankton
•
Unicellular protists have been broadly divided in to three major groups
Photosynthetic protists : e.g., Dinoflagellates, Diatoms, Euglenoids. Consumer protists : e.g., Slime moulds or Myxomycetes. Protozoan protists e.g., Zooflagellata, Sarcodina, Sporozoa, Ciliata Chrysophytes: •
This group includes diatoms and golden algae (desmids).
•
They are found in fresh water as well as in marine environments. They are microscopic and float passively in water currents (plankton).
•
In diatoms the cell walls form two thin overlapping shells, which fit together as in a soap box. The walls are embedded with silica and thus the walls are indestructible. Thus, diatoms have left behind large amount of cell wall deposits in their habitat; this accumulation over billions of years is referred to as ‘diatomaceous earth’, Being gritty this soil is used in polishing, filtration of oils and syrups. Diatoms are the chief ‘producers’ in the oceans.
Dianoflagellates •
These organisms are mostly marine and photosynthetic.
•
They appear yellow, green, brown, blue or red depending on the main pigments present in their cells. The cell wall has stiff cellulose plates on the outer surface.
•
Most of them have two flagella; one lies longitudinally and the other transversely in a furrow between the wall plates. Very often, red dianoflagellates (Example: Gonyaulax) undergo such rapid multiplication that they make the sea
•
appear red (red tides). Toxins released by such large numbers may even kill other marine animals such as fishes.
•
Dinoflagellates reproduce asexually through cell division or by the formation of zoospores and cysts. The cell division starts from posterior end. During cell division, centromeres and spindle are not seen.
•
The spindle is replaced by cytoplasmic microtubules. During mitosis, the chromosomes break up into pairs of chromatids. The nuclear envelops and nucleolus persists during division.
•
If sexual reproduction occurs, it is isogamous or anisogamous. Two cells conjugate by a conjugation canal where the two amoeboid gametes fuse to form a diploid zygote. Life cycle involves zygotic meiosis (e.g., Ceratium, Gyninodinium etc.) or gametic meiosis (e.g., Noctiluca), Euglenoids
•
Majority of them are fresh water organisms found in stagnant water.
•
Instead of a cell wall, they have a protein rich layer called pellicle which makes their body flexible.
•
They have two flagella, a short and a long one. Though they are photosynthetic in the presence of sunlight, when deprived of sunlight they behave like heterotrophs by predating on other smaller organisms. Interestingly, the pigments of euglenoids are identical to those present in higher plants. Example: Euglena.
36 •
Biology________________________________________________________________________________ The two flagella join with each other at a swelling called paraflagellar body. An orange red coloured eye-spot or stigma is located at the base of flagellum attached to the membrane of reservoir af the level of paraflagellar body. They contain red pigment as taxanthin. Both paraflagellar body and eye spot act as photoreceptors and direct the organism towards the optimum light.
•
Nutrition is holophytic (photoautotrophic), saprobic (e.g., Rhabdomonas) or holozoic (e.g.Peranema). Even holophytic forms can pick up organic compounds from the outside medium. Such a mode of nutrition is called mixotrophic.
•
Euglena is a connecting link between animals and plants.
•
Nutrition in Euglena is mixotrophic, when light is available it is photosynthetic, in darkness it is saprophytic absorbing food from surrounding water
Slime Moulds •
Slime moulds are saprophytic protists. The body moves along decaying twigs and leaves engulfing organic material.
•
Under suitable conditions, they form an aggregation called plasmodium which may grow and spread over several feet. During unfavourable conditions, the plasmodium differentiates and forms fruiting bodies bearing spores at their tips. The spores possess true walls. They are extremely resistant and survive for many years, even under adverse conditions. The spores are dispersed by air currents.
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Biology________________________________________________________________________________
Slime moulds are of two types Acellular (Plasmodial) Slime moulds •
Acellular slime moulds commonly grow as slimy masses on damp places rich in dead and decaying organic matter
•
The somatic phase is diploid and consists of a free living organic matter multinucleated protoplasm called plasmodium.
•
The plasmodium slowly streams or glides over decaying organic matter putting out blunt finger like pseudopodia showing amoeboid movement.
•
They also absorb dissolved organic substances from the substratum showing saprotrophic nutrition.
•
Under unfavourable conditions the plasmodium contracts and gets surrounded by thick horny wall. It is called sclerotium.
•
Each plasmodium reproduces asexually by the formation of several, small, sessile or stalked, brightly coloured sporangia.
•
The multinucleated protoplasm of sporangium is cleaved to produce a large number of small uninucleate spores.
Cellular Slime moulds •
The cellular slime moulds occurs in the form of haploid uninucleated, naked (without cell wall) cell covered by plasma membrane. These cells are called myxamoebae.
•
The myxamoebae move freely. with the help of amoeboid movement and phagotrophic or holozoic nutrition.
•
They grow and divide to form a large population of individuals.
38 •
Biology________________________________________________________________________________ Under unfavourable condition a myxamoeba secrete a rigid cellulose wall to form the microcyst. Microcyst formation is a means of perennation.
ProtozoanS •
All protozoans are heterotrophs and live as predators or parasites. They are believed to be primitive relatives of animals. There are four major groups of protozoans.
•
Amoeboid protozoans: These organisms live in fresh water, sea water or moist soil. They move and capture their prey by putting out pseudopodia (false feet) as in Amoeba. Marine forms have silica shells on their surface. Some of them such as Entamoeba are parasites. Amoeba
•
Amoeba belongs to the class Sarcodina or Rhizopoda of the phylum protozoa. It is discovered by Russel Von Rosenhoff in 1755.
•
The most common species of Amoeba proteus. Proteus is the name of the mythical sea god who could change shape.
•
Amoeba is cultured in laboratory by Hay infusion method.
•
Body is covered by plasmalemma. It is a trilaminar and selectively permeable membrane.
•
Plasmalemma is excretory, ammonia diffuses out through it. It is also respiratory diffusion of oxygen and carbon dioxide takes place through it.
•
The body bears a member of temporary and blunt pseudopodia. The type of pseudopoium found in Amoeba proteus is lobopodium. Pseudopodia are composed of both ectoplasm and endoplasm.
•
Pseudopodium at its forward end gets its from consistency by hyaline cap which is made of ectoplasm.
•
Pseudopodia in Amoeba are meant for feeding and locomotion.
•
Pseudopodia are found in Amoeba and leucocyte of higher animals.
•
Locomotion of Amoeba is known as amoeboid movement. Sol gel theory of amoeboid movement was first given by Hyman supported by Pantin and Mast. According to this theory amoeboid locomotion is due to change in the velocity of cytoplasm.
•
Digestion in Amoeba is intracellular. Amoeba secretes digestive enzymes for hydrolysing starch, protein, fat etc.
39 •
Biology________________________________________________________________________________ Food vacuole of Amoeba is analogous to the alimentary canal of an animal or gastro vascular cavity of Hydra. The contents of food vacuole in Amoeba first becomes acidic then alkaline.
•
Egestion of undigested food in Amoeba takes place through a temporary rupture of the surfacç membrane.
•
Amoeba responds to environmental conditions. Response to the stimuli is called taxis. Different taxis are thermotaxis (temperature) phototaxis (light), thigmotaxis (touch), chemataxis (chemicals), galvanotaxis (electric current), geotaxis (gravity) and rheotaxis (water current).
•
Flagellated protozoans: The members of this group are either free-living or parasitic. They have flagella. The parasitic forms cause diaseases such as sleeping sickness. Example: Trypanosoma.
•
Trypanosoma gambiense is the parasite zooflagellate which causes one of the deadliest ailments in human beings called African sleeping sickness or Trypanosomiasis. It was discovered by Frode in 1901.
•
Trypanoso ma is usually found in the blood of vertebrates, finally invading cerebrospinal fluid.
•
Trypanosoma is an endoparasite, blood parasite, extra cellular parasite.
•
Trypanosoma is digenetic, it completes its life cycle in two hosts. The primary or principal or definite host is man and the intermediate or secondary host or vector is the insect, tse-tse fly or bug
•
Ciliated protozoans: These are aquatic, actively moving organisms because of the presence of thousands of cilia. They have a cavity (gullet) that opens to the outside of the cell surface. The coordinated movement of rows of cilia causes the water laden with food to be steered into the gullet. Example: Paramecium.
40 •
Biology________________________________________________________________________________ Paramecium is commonly called as ‘Slipper animalcule’, Body is distinguished into an oral or ventral surface and an aboral or dorsal surface.
•
Body is covered with a thin, firm, flexible membrane called pellicle. Entire body surface is covered by numerous cilia, the locomotory organelles. Cilia in the posterior end are longer called caudal tuft. Each cilium arises from a basal granule or kinetosome, Paramecium has infraciliary and neuromotor system to co-ordinate ciliary beat.
•
Digestion in paramecium is intracellular. Food vacuole constantly moves along a definite courses (cyclosis) wi thin streaming endoplasm. Food vacuole is digested in the cell body in acidic to alkaline media. Egestion of undigested food takes place through cytopyge or cytoproct, a temporary formed anus.
•
Paramecium reproduces by transverse binary fission and nuclear reorganisation. Binary fission occurs during favourable condition. In this process, macronucleus divides amitotically and micronucleus mitotically.
•
Sporozoans: This includes diverse organisms tha have an infectious spore-like stage in their life cycle The most notorious is Plasmodium (malaria pJrasite) which causes malaria which has staggering effect on human population. Plasmodium Systematic position
Phylum
Sub-phylum
Protozoa
Plasmodroma
Class
Sporozoa
Sub-class
Telosporidia
Order
vivax
Genus
Haemosporidia
Species
Plasmodium
41 •
Biology________________________________________________________________________________ Laveran (1880) discovered that malaria Is cause by a protozoan parasite, Plasmodium vivax. Sir Ronald Ross was (1896) the first to observ oocytes of plasmodium in female Anapheles.
•
Life cycle : During life cycle two important phases are present.
(1) EndOgenous or Asexual phase passes in man. (2) Exogenous or Sexual phase : passes in female Anopheles mosquito
KINGDOM FUNGI •
The fungi constitute a unique kingdom of heterotrophic organisms. They show a great diversity in morphology and habitat.
42 •
Biology________________________________________________________________________________ Some unicellular fungi, e.g., yeast are used to make bread and beer. Other fungi cause diseases in plants and animals; wheat rust-causing Puccinia is an important example. Some are the source of antibiotics, e.g., Penicillium.
•
Fungi are cosmopolitan and occur in air, water, soil and on animals and plants. They prefer to grow in warm and humid places.
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With the exception of yeasts which are unicellular, fungi are filamentotis. Their bodies consist of long, slender thread-like structures called hyphae. The network of hyphae is known as mycelium. Some hyphae are continuous tubes filled with multinucleated cytoplasm — these are called coenocytic hyphae. Others have septic or cross walls in their hyphae. The cell walls of fungi are composed of chitin and polysaccharides.
•
Most fungi are heterotrophic and absorb soluble organic matter from dead substrates and hence are called saprophytes. Those that depend on living plants and animals are called parasites. They can also live as symbionts — in association with algae as lichens and with roots of higher plants as mycorrhiza.
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Reproduction in fungi can take place by vegetative means — fragmentation, fission and budding.
•
Asexual reproduction is by spores called conidia or sporangiospores or zoospores, and sexual reproduction is by oospores, ascospores and basidiospores. The various spores are produced in distinct structures called fruiting bodies.
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The sexual èycle involves the following three steps:
•
Fusion of protoplasms between two motile or non-motile gametes called plasmogamy.
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Fusion of two nuclei called karyogamy.
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Meiosis in zygote resulting in haploid spores.
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When a fungus reproduces sexually, two haploid hyphae of compatible mating types come together and fuse. In some fungi the fusion of two haploid cells immediately results in diploid cells (2n). However, in other fungi (ascomycetes and basidiomycetes), an intervening dikaryotic stage (n + n i.e. two nuclei per cell) occurs; such a condition is called a dikaryon and the phase is called dikaryophase of fungus. Later, the parental nuclei fuse and the cells become diploid. The fungi form fruiting bodies in which reduction division occurs, leading to formation of haploid spores.
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The classification of fungi based on the characteristics of the life cycle involved like.
•
Nature of somatic phase, kinds of asexual spores, kinds of sporangia, nature of the life cycle and presence or absence of perfect or sexual stage
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Biology________________________________________________________________________________
Phycomycetes Members of phycomycetes are found in aquatic habitats and on decaying wood, in moist and damp places or as obligate parasites on plants. The mycelium is aseptate and coenocytic. Asexual reproduction takes place by zoospores (motile) or by aplanospores (non-motile). These spores are endogeneously produced in sporangium. Zygospores are formed by fusion of two gametes. These gametes are -similar in morphology (isogamous) or dissimilar (anisogamous or oogamous). Examples: Mucor, Rhizopus and Albugo (the parasitic fungi on mustard). Rhizopus/Mucor They are cosmopolitan and saprophyti’c fungus, living on dead organic matter. Rhizopus stolonifer occur very frequently on moist bread, hence commonly called black bread mold. Mucor is called dung mold. Both are called black mold or pin mold because of black coloured pin head like sporangia. Besides, it appears in the form of white cottony growth on moist fresh organic matter, jams, jellies, cheese, pickles, etc.. Reproduction : They reproduces by vegetative, asexual and sexual methods. (1) Vegetative reproduction : It takes place by fragmentation. If stolon breaks accidentally into small segments, each part grows into a new mycelium. (2) Asexual reproduction : It occurs by three types of non-motile mitospores, sporangiospores, chlamydospores and oidia (3) Sexual reproduction : Sexual reproduction takes place by conjugation between two multinucleate but single celled gametangia. The gametes are isogamous and non-motile.
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Biology________________________________________________________________________________
Economic importance (1) Spoilage of food: Exposed bread and other food particles are spoiled by Rhizo pus. (2) Soft rot: rhizopus species attack sweet potato, apple and strawberry producing soft rot or leak disease. Germinating maize grains are also attacked. (3) Mucormycosis Mucor pusillus and M. ramosissimus may attack internal human organs, including lungs alimentary canal and nervous system. (4) Fermented foods : Temph (a solid food from soyabean) and sufu (Chinese cheese) are prepaired with the help of Rhizopus and ivtucor respectively. (5) Chemicals : Citric acid prepared fry Mucor from molasses, furnaric acid and cortisone by Rhizopus stolon(fer, Lactic acid by R. stolonifer and R.nodosus and alcohol by R. oryzae and M. javanicus. (6) Antibiotic : Ramysin is produced by Mucor ramannianus. (7) Waste water treatment: Growth of Mucor arrhizus removes heavy metal contamination of water. ALBUGO Albugo is a member of phycomycetes. It is an obligate parasite and grows in the intercellular spaces of host tissues. It is parasitic mainly on the members of families Cruciferae, Compositae, Amaranthaceae and Convolvulaceae, The disease caused by this fungus is known as white rust or white blisters. The most common and well known species is Albugo candida which attacks the members of the mustard family (Cruciferae). It is commonly found on Capsella bursa pastoris (Shepherd’s purse) and occasionally on radish, mustard, cabbage, cauliflower, etc. The reserve food is oil and glycogen. Ascomycetes Commonly known as sac-fungi, the ascomycetes are unicellular, e.g., yeast (Sacharomyces) or multicellular, e.g., Penicillium. They are saprophytic, decomposers, parasitic or coprophilous (growing on dung). Mycelium is branched and septate. The asexual spores are coriidia produced exogenously on the special mycelium called conidiophores. Conidia on germination produce mycelium. Sexual spores are called ascospores which are produced endogenously in sac like asci (singular ascus). These asci are arranged in different types of fruiting bodies called ascocarps.
45
Biology________________________________________________________________________________
Some examples are Aspergillus, Claviceps and Neurospora. Neurospora is used extensively in biochemical and genetic work, Many members like morels and buffles are edible and are considered delicacies. Yeast : Yeast was first described by Antony Von Leeuwenhoek in 1680. Yeast are nonmycelial or unicellular, which is very small and either spherical or oval in shape. However, under favourable conditions they grow rapidly and form false mycelium or pseudomycelium. Individual cells are colourless but the colonies may appear white, red, brown, creamy or yellow. The single cell is about 10 lAm in diameter. It is enclosed in a delicate membrane which is not made up of fungal cellulose but is a mixture of two polysaccharides known as mannan and glycogen. Reproduction Yeast reproduces by vegetative or asexual and sexual methods. Vegetative reproduction Yeast reproduce vegetatively either by budding or by fission. Sexual reproduction Sexual reproduction in yeasts takes place during unfavourable conditions, particularly when there is less amount of food. The sex organs are not formed in yeasts and the sexual fusion occurs between the two haploid vegetative cells or two ascospores which behave as gametes. The two fusing gametes are haploid and may be isogamous or anisogamous. Such kind of sexual reproduction is called gametic copulation. It is the best example of hologamy i.e., the entire vegetative thallus is transformed into reproductive body. The sexual fusion leads to the formation of diploid zygote. The zygote behaves as an ascus and forms 4 — 8 haploid ascospores. These liberate and function as vegetative cells. Economic importance Useful activities Baking industry: Yeast are used in manufacture of bread. Kneaded flour is mixed with yeast and allowed to ferment. Yeast convert starch into sugars and sugar into CO2 and alcohol with help of enzyme zymase, CO2 is released when effervescence takes place due to which bread become spongy and gets swollend and is of light weight. Brewing industry: Brewer’s yeast or Beer yeast is Saccharomyces cerevisiae and wine yeast is SaccharomycS ellipsoidens. They perform alcoholic fermentation. yeast C6 H12O6 → C2 H 5OH + 2CO2 Zymase
Food yeast Yeast from brewing industry is harvested and used as food yeast. It is rich in protein and vitamins-B (Riboflavin). Special food yeasts are Torulopsis (protein), Endomyces (fat) and Cryptococus (both). Harmful activities Fermentation of fruits and fruit juices by yeast cells makes their taste unpleasent. Parasitic species of yeast like Nematospora causes diseases in tomato, cotton and bean. Parasitic yeast cause diseases in human beings (e.g. cryptococcois, blastomycosis and torulosis).
46
Biology________________________________________________________________________________
Basidiomycetes * Commonly known forms of basidiomycetes are mushrooms, bracket fungi or puffballs. They grow in soil, on logs and free stumps and in living plant bodies as parasites, e.g., rusts and smuts. The mycelium is branched and septate. * The asexual spores are generally not found, but vegetative reproduction by fragmentation is common. The sex organs are absent, but plasmogamy is brought about by fusion of two vegetative or somatic cells of different strains or genotypes. The resultant structure is dikaryotic which ultimately gives rise to basidium. Karyogamy and meiosis take place in the basidium producing four basidiospores. The basidiospores are exogenously prQduced on the basidium. The basidia are arranged in fruiting bodies called basidiocarps. * Some common members are Agaricus (mushroom), Ustilago (smut) and Puccinia (rust fungus). Deuteromycetes * Commonly known as imperfect fungi because only the asexual or vegetative phases of these fungi are known. * The deuteromycetes reproduce only by asexual spores known as conidia. The mycelium is septate and branched. Some members are saprophytes or parasites while a large number of them are decomposers of lifter and help in mineral cycling. * Examples Alternaria, Colletotrichum and Trichoderma. KINGDOM PLANTAE * Kingdom Plantae includes all eukaryotic chlorophyll-containing organisms commonly called plants. * A few members are partially heterotrophic such as the insectivorous plants or parasites. Bladderwort and Venus fly trap are examples of insectivorous plants and Cuscuta is a parasite. * The plant cells have an eukaryotic structure with prominent chloroplasts and cell wall mainly made of cellulose. Life cycle of plants has two distinct phases — the diploid sporophytic and the haploid gametophytic that alternate with each other. The lengths of the haploid and diploid phases, and whether these phases are free—living or dependent on others, vary among different groups in plants. This phenomenon is called alternation of generation.
Classification of plantae August Wilhelm Eichler (1883) a Vinnese botanist, divided plant kingdom into two sub-kingdoms mainly on the basis of presence or absence of seeds.
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(1) Cryptogamae (Cr. Cryptos = hidden; gamos = marriage) Lower plants in which sex organs are hidden and seeds and flowers absent. It includes Thallophytes, Bryophytes, Pteridophytes. (2) Phanerogamae (Cr. Phaneros = visible; gamos marriage) Higher plants in which sex organs are evident seeds present. It includes Gymnosperms and Angiosperms. Engler (1886) divided plants into Thallophyta (plant body thallus like and there is no embryo formation) and Embryophyta (zygote develops into multicellular embryo). Thallophyta (Cr. Thallos = undifferentiated; phyton = plant). This term was coined by Endlicher (1836). It includes Algae, Fungi, Bacteria, Lichens. Unger (1838) placed algae, fungi and lichens under thallophyta. In modem system of clasification like Whittaker (1969), Fungi, Lichens and Bacteria are excluded from this group and are placed in separate kingdoms. KINGDOM ANIMALIA •
This kingdom is characterised by heterotrophic eukaryotic organisms that are multicellular and their cells lack cell walls.
•
They directly or indirectly depend on plants for food. They digest their food in an internal cavity and store food reserves as glycogen or fat.
•
Their mode of nutrition is holozoic — by ingestion of food.
•
They follow a definite growth pattern and grow into adults that have a definite shape and size.
•
Higher forms show elaborate sensory and neuromotor mechanism.
•
The sexual reproduction is by copulation of male and female followed by embryological development.
•
Ariaima Animals without red blood e.g., sponges, cnidaria, mollusca, arthropoda, echinodermata, etc.
•
Enaima Animals with red blood e.g., vertebratc7
•
Vivipara Animals which give birth to young ones are included in this subgroup e.g., man, dogs, cows,etc
•
Ovipara : Animals which lay eggs are included in this subgroup e.g., frogs, toads, lizards, snakes, birds, etc.
Anamniotes Vertebrates without embryonic membranes e.g., fishes, amphibians. * Amniotes Vertebrates with embryonic membranes (chorion, amnion, allantois, yolk sac) e.g., reptiles, birds, mammals. * Acraniata or Protochordata Chordates without cranium (brain box). It includes urochordata and cephalochordata. Chordates Animals with notochord dorsal tubular nerve cord, paired pharyngeal gill slits. All urochordates, cephalochordates and vertebrates are called chordates. * Craniata or Vertebrate : Chordates with cranium. It includes cyclostomes, pisces, amphibians, reptiles, birds and mammals. * Nonchordates Animals without notochord (a rod like elastic structure which supports the body). Phylum Porifera to phrlum Hemichordata are called nonchordates. Invertebrates Animals without vertebral colounin (backbone). All the nonchordates, urochordates and cephalochordates are callectively called invertebrates. VIRUSES, VIROIDS AND LICHENS * The viruses are non-cellular organisms that are characterised by having an inert crystalline structure outside the living cell. Once they infect a cell they take over the machinery of the host cell to replicate themselves, killing the host.
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* The name virus that means venom or poisonous fluid was given by Pasteur. D.J. Ivanowsky (1892) recognised certain microbes as causal organism of the mosaic disease of tobacco. These were found to be smaller than bacteria because they passed through bacteria-proof filters. * M.W. Beijerinek (1898) demonstrated that the extract of the infected plants of tobacco could cause infection in healthy plants and called the fluid as Contagium vivum fluidum (infectious living fluid). * W,M. Stanley (1935) showed that viruses could be crystallised and crystals consist largely of proteins. They are inert outside their specific host cell. * Viruses are obligate parasites. * In addition to proteins viruses also contain genetic material, that could be either RNA or DNA. No virus contains both RNA and DNA. A virus is a nucleoprotein and the genetic material is infectious. In general, viruses that infect plants have single stranded RNA and viruses that infect animals have either single or double stranded RNA or double stranded DNA. Bacterial viruses or bacteriophages (viruses that infect the bacteria) are usually double stranded DNA viruses. The protein coat called capsid made of small subunits called capsomeres, protects the nucleic acid. These capsomeres are arranged in helical or polyhedral geometric forms. Viruses cause diseases like mumps, small pox, herpes and influenza. AIDS in humans is also caused by a virus. In plants, the symptoms can be mosaic formation, leaf rolling and curling, yellowing and vein clearing, dwarfing and stunted growth. Viroids: In 1971 T,O, Diener discovered a new infectious agent that was smaller than viruses and caused potato spindle tuber disease. It was found to be a free RNA; it lacked the protein coat that is found in viruses, hence the name viroid. The RNA of the viroid was of low molecular weight. Lichens : Lichens are symbiotic associatiohs i.e. mutually useful associations, between algae and fungi. The algal component is known as phycobiont and fungal component as mycobiont, which are autotrophic and heterotrophic, respectively. Algae prepare food for fungi and fungi provide shelter and absorb mineral nutrients and water for its partner. Lichens are very good pollution indicators — they do not grow in polluted areas.
NOTE: In Linnaeus’ time a Two Kingdom system of classification with Plantae and Animalia kingdoms was developed that included all plants and animals respectively. This system did not distinguish between the eukaryotes and prokaryotes, unicellular and multicellular organisms and photosynthetic (green algae) and non- photosynthetic (fungi) organisms.
* RH. Whittaker (1969) proposed a Five Kingdom Classification. The kingdoms defined by him were named Monera, Protista, Fungi, Plantae and Animalia. The main criteria for classification used by him include cell structure, thallus organisation, mode of nutrition, reproduction and phylogenetic relationships. Characteristics of five kingdoms
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Exercise-1 1. Eichler divided plant kingdom in: (1) Two divisions
(2) Four divisions
(3) Five divisions
(4) Ten divisions
2. A. P. De-Candolle classified plants on the basis of (1) Vascular tissues
(2) Embryo
(3) Stem
(4) Flower
3. Edward Bessey proposed a new name for dicots, it was — (1) Magnoliophyta
(3) Oppositifolia
(2) Anthophyta
(4) Alternifolia
4. Embryophyta includes — (1) Angiosperms only
(2) Algae and fungi
(3) Bryophyta & Pteridophyta
(4) All plants except thallophyta
(3) Chlorophyta
(4) Cyanophyta
(3) Phaeophyta
(4) Myxomycophyta
(3) Bentham & Hooker
(4) Bessey
5. According to Tippo, BGA is included in: (1) Chrysoplhyta
(2) Pyrrophyta
6. Oswald Tippo placed slime molds in: (1) Cyanophyta
(2) Chlorophyta
7. ‘Genera Plantarum” was written by — (1) Engler and Prantal (2) Hutchinson
8. Angiosperms (dicotyledons) were distinguished into archichlamydae and metachlamydae by — (1) Candolle
(2) Hutchinson
(3) Engler and Prantl
(4) None
9. Chief merit of Bentham and Hooker’s classification is that— (1) It is a system mostly based on evolutionary concepts (2) It is a natural systems of classification of all groups of plants (3) The description of the taxa are based on actual observation of the specimen (4) It also considers the phylogenetic aspects 10. Bantham and Hooker classified dicots into — (1) Polypetalae, gamopetalae and glumiflorae (2) Polypetalae, gamopetalae and monochlamyqae (3) Achlamydae, diclamydeae and metachlamydae (4) Archichlamydae, sympetalae & apetalae 11. Zoodiogama includes — (1) Gymnosperms and pteridophyta
(2) Dicots, monocots, gymnosperm
(3) Bryophyta and pteridophyta
(4) Only thallophyta
12. Four kingdom system of classification was proposed by — (1) Whittaker
(2) Copeland
(3) Linnaeus
(4) Oswald Tippo
13. In two kingdom system of classification Euglena is included in — (1) Animalia
(2) Plantae
(3) Both the above (4) Protista
14. The system of classification proposed by Bentham and Hooker is — (1) Artificial
(2) Natural
(3) Phylogenetic
15. The classification of Linnaeus was mainly based
(4)Numerica1
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(1) Sepals
(2) Carpels
(3) Petals
(4) Stamens
(3) Bryophyta
(4) All of these
16. Kingdom monera comprises the — (1) Plants of economic importance (2) AU the plants studied in botany (3) Prokaryotic organisms (4) Plants of Thallophyta group 17. Embryophyta include: (1) Algae
(2) Fungi
18. Whittaker is famous for — (1) Two kingdom classification (2) Four kingdom classification (3) Five kingdom classification (4) Distinguishing in Bacteria & blue green Algae 19. First phylogenetic system of plant classification was given by — (1) Engler and Prantl
(2) Eichler
(3) Ostwald Tippo (4) Bentham & Hooker
20. System of classification proposed by Linnaeus was (1) Artificial
(2) Natural
(3) Sexual (4) (1) and (3) both
21. “Die Naturlichen Pflanzen familien’ wrote by — (1) Eichler
(2) Linnaeus
(3) Engler and Pranti
(4) Bentham and Hooker
22. Engler and Prantl created metachlamydae to include — (1) Polypetalous dicots (2) Gamopetalous dicots
(3) Gamopetalous monocots
(4) Gymnosperm
23. In which of the following systems, plants are classified in geneological order — (1) Artificial
(2) Natural
(3) Phylogenetic
(4) Non-phylogenetic
24. Which book is the starting point for phylogenetic system— (1) Origin of species (2) Die Naturlichen Pflanzen familien (3) The phylogenetic taxonomy of flowering plants (4) Historia plantarum 25. Which of the following taxonomists first employed the characteristics of vascular tissue in taxonomy (1) Tippo
(2) Engler and Prantl
(3) Takhtajan
(4) A.P. de Candolle
26. The group “Pteropsida’ proposed by Oswald Tippo includes — (1) Ferns
(2) Gymnosperms
(3) Angiosperms
(4) All the above
27. In Whittaker’s five kingdom classification, eukaryotes were assigned to — (1) All the five kingdom (2) Only four of the five kingdoms (3) Only three kingdom (4) Only one kingdom 28. The book genera plantarum which contains the, classification of seed plants was wrote by —
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(1) Linnaeus
(2) De jussieu
(3) Bentham and Hooker
(4) Eichler
29, “Theorie elementaire de la botanique is the book of: (1) Takhtajan
(2) De Candolle
(3) Eichler
(4) Linnaeus
30. Carolus Linnaeus classified plant kingdom on the basis of— (1) Roral morphology
(2) Overall morphology of plants
(3) Type of sexual reproduction
(4) Anatomical character
31. Serology can be used to know the phylogenetic relationship of — (1) Plants
(2) Animals
(3) Both the above
(4) Dinosours
32. According to Bessey which of the following is not an advanced character of higher plants ? (1) Gamopetalous condition
(2) Herbaceous habit
(3) Monocotyledon form
(4) Woody nature (Tree habit)
33. Which of the following book was written by Theophrastus? (1) Enquiry in to plants
(2) Causes of Plants
(3) Historia plantarum
(4) AU the above
34. Who proposed the new name for dicots and monocols on the basis of phyllotaxy? (1) Linneaus
(2) Oswald Tippo
(3) Edward Bessey
(4) Theophrastus
35. Whittaker placed prokaryotes and akaryotes in (1) Protista
(2) Protozoa
(3) Plantae
(4) Monera
36. Oswald-Tippo included how many divisions in sub kingdom thallophyta? (1) 20 – divisions
(3) 7 – divisions
(2) 10 – divisions
(4) 2 - divisions
37. First plant classification was given by — (1) Linneaus
(2) John-Ray
(3) Theophrastus
(4) Darwin
38. Division “Tracheophyta” includes — (1) Bryophyta (2) All vascular plants (3) All non-vascular plants
(4) All non-vascular and vascular plants
39. Which group of plant have embryo but not vascular tissue— (1) Cyanophyta
(2) Tracheophyta
(3) Bryophyta
(4) Chlorophyta
40. According to Benthum & Hooker total families of real flowering plants — (1) 202
(2) 199
(3) 34
(4) 85
4L Who gave importance of serology in taxonomy ? (1) Willis
(2) Karl Menz (3) Hutchinson (4) Whittaker
42. The word Cryptogamia was coined by — (1) Theophrastus
(2) Linnaeus
(3) Bentham & Hooker (4) John-Ray
43. Siphonogama includes — (1) Bryophyta and thallophyta (2) Pteridophyta & bryophyta (3) Gymnosperm & angiosperm (4) Thallophyta and gymnosperm 44. The phylogenetic relationship among organisms can be established by the technique — (1) Autoradiography
(2) X-ray crystallography
(3) Serology
(4) Genealogy
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45. According to four kingdom systçm of Copeland, the fungi belong to kingdomS — (1) Protista
(2) Mychota
(3) Mycota
(4) Plantae
46. According to Oswald Tippo Angiosperms are placed under — (1) Atracheata
(2) Thallophyta
(3) Tracheophyta
(4) Spermatophyta
(3) Linnaeus
(4) Oswald & Tippo
47. “Systema Naturae” book was written by — (1) Angler and prantle
(2) Darwin
48. According to Eichler cryptogamia includes — (1) Gymnosperm and Angiosperm
(2) Thallophyta and Gymnosperm
(3) Thallophyta, Bryophyta and Pteridophyta
(4) Only angiosperm
49. According to Whittaker kingdom monera includes (1) Unicellular eukaryotes
(2) Prokaryotes & akaryotes
(3) Slime molds & protozoa
(4) Multicellular & eukaryotes
50. ‘Cellular plants’ and ‘Vascular plants” are the groups created by — (1) Tippo
(3) Takhtajan
(2) Eichler
(4) De candolle
51. According to Copeland the Red algae belongs to (1) Monera
(2) Protista
(3) Plantae
(4) Animalia
52. Linnaeus proposed an outline of plant classification in (1) Genera Plantarum
(2) Species Plantarum (3) Systema Naturae (4) Philosophia Botanica
53. Who classified the Embryophyta on the basis of fertilization ? (1) Eichler
(2) Tippo
(3) Takhtajan
(4) Engler & Prantl
54. The earliest serious efforts to classify the living things were made by — (1) Greek philosophers
(2) Latin American scientist
(3) British herbalists
(4) Indian Hakims
55. Classification proposed by Bentham and Hooker is mainly based on — (1) Embryological characters
(2) Aoral characters
(3) Vegetative: characters
(4) Phylogenetic characters 56. The separation of living beings into five kingdoms is based on — (1) Complexity of cell structure
(2) Complexity of organism’s body
(3) Mode of obtaining nutrition
(4) All the above
57. Which of the following organisms were never included in protista ? (1) Bacteria
(2) Red algae
(3) Slimemolds
(4) Mosses
58, In which book, Linnaeus proposed the principles of nomenclature 7 (1) Species plantarum
(2) Systema Naturae
(3) Rora lapponica
(4) Philosophia botanic
59. According to Bessey the tree habit is a — (1) Advance character (2) Primitive character (3) Degenerate character 60. Which of the two groups includes the similar plants (1) Siphonogama and spermatophyta (2) Siphonogama and zoodiogama (3) Metachlamydae and monochlamydae
(4) Any of the above
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(4) Polypetalae and gamopetalae 61. In Tippo’s classification the group a tracheata includes (1) Thallophyta
(2) Bryophyta
(3) All the vascular plants
(4) All the non-vascular plants
62. Phylogenetic relationship of plants can be established by: (1) Plantserum
(2) Animal serum
(3) Chromatography
(4) Autoradiography
(3) Only bryophyta
(4) Only pteridophyta
63. Fertilization by zoodiogamy occurs in — (1) Cryptogams
(2) Phanerogams
64. Swedish botanist who proposed the artificial system of classification on the basis of floral morphology was — (1) De-Jussieu
(2) Bentham and Hooker
(3) John Ray
(4) Carl von linne
(3) Fungi
(4) Plantae
65. Kingdom of unicellular eukaryotes (1) Monera
(2) Protista
66, Who among the following proposed a classification in which plants with one stamen were placed under the class Monandria, with two in Diandria and with many stamens in polyandria (1) Hutchinson
(2) Bentham and Hooker
(3) Cronquist
(4) Lirinaeus
67. Polypetalae,Gamopetalae and monochlamydae are subclasses of — (1) Dicotyledonae
(2) Gymnospermae
(3) Monochlamydae (4) Siphanogama
68. A person who studies about the origin, evolution and variations in plants and also about the classification of plants, is called as — (1) Classical taxonomist
(2) Herbal taxonomist
(3) a-taxonomist
(4) (3-taxonomist
69. Who proposed phylogenetic classification of plants (1) Linnaeus
(2) Hutchinson
(3) Bentham and Hooker
(4) Mehta
70. In Whittaker’s ‘Five Kindom Classification’, eukaryotes were assigned to — (1) Only two of the five kingdoms
(2) Only three of the five kingdoms
(3) Only four of the five kingdoms
(4) All the five kingdoms
71. Most important criteria used for the present day classification of living organisms is based on — (1) Presence and absence of notochord
(2) Resemblances in external features
(3) Breeding habits
(4) Anatomical and physiological characteristics
72. The term “phylum” in animal classification was coined by (1) E. Haeckel
(2) John Ray
(3) G.L. Cuvier
(4) Carolus Linnaeus
73. Species living in different geographical areas are (1) Sibling species
(2) Morphospecies
(3) Sympatric species
(4) Allopatric species
(3) Naming
(4) Classification
74, First act in taxonomy is — (1) Description
(2) Identification
75. Two morophologically similar populations are intersterile. They belong to — (1) One species
(2) Two biospecies
(3) Two sibling species (4) None of the above
76. A true species consists of a population — (1) Sharing the same niche
(2) Interbreeding
(3) Feeding over the same food
(4) Reproductivity isolated
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77. Phenetic classification of organisms is based on (1) Dendogram based on DNA characteristics
(2) Sexual characteristics
(3) Observable characteristics o existing organisms
(4) The ancestral lineage of existing organisms
78. Barophillic prokaryotes — (1) Grow slowly in highly alkaline frozon lakes at high altitudes (2) Occur in water containing high concentrations of barium hydroxide (3) Grow and multiply in very deep marine sediments (4) Readily grow and divide in sea water enriched in any soluble salt of barium.
DIRECTIONS for Qs. 79 to 88: Each questions contain STATEMENT-I (Assertion) and STATEMENT-2 (Reason), Each question has 4 choices (1), (2), (3) and (4) out of which ONLY ONE is correct (1) Statement- 1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1 (2) Statement -1 is True, Statement -2 is True Statement-2 is NOT a correct explanation for Statement - 1 (3) Statement - I is True, Statement- 2 is False (4) Statement -1 is False, Statement -2 is False 79. Statement 1 Systematics is the branch of biology that deals with classification of living organisms. Statement 2 : The aim of classification is to group the organisms. 80. Statement I Acraniata is a group of organisms which do not have distinct cranium. Statement 2 : It includes small marine forms without head. 81, Statement 1 : To give scientific name to plant, there is ICBN. Statement 2 It uses articles, photographs and recommendations to name a plant. 82. Statement 1 : Bacteria are prokaryotic. Statement 2 : Bacteria do not possess true nucleus and membrane bound cell organelles. 83. Statement 1 : Bacteria have three basic shapes, i.e., round, rod, spiral. Statement 2 : Cocci and Bacilli may form clusters or chain of a definite length. 84. Statement I : Bacterial photosynthesis occurs by utilizing wavelength longer than 700 nm. Statement 2: Here reaction centre is B-890 85. Statement 1: The plasmodium often possesses a number of branched “veins”. Statement 2 : The position of “veins’ remains fixed. 86. Statement 1 Sandfly transmits Kala-azar. Statement 2 In Kala-azar, the parasite damages the brain 87. Statement 1 Symbiosis is furnished by mycorrhiza. Statement 2 : In mycorrhiza, symbiosis is established between fungus and alga. 88. Statement 1 : Aflatoxins are produced by Aspergitlusfiavus. Statement 2 These toxins are useful to mankind.
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ANSWER KEY
HINTS & SOLUTION (4) (4) Embryophyta includes thallophyta all plants except (10) (2) Bentham and Hooker classified dicots into Polypetalae, gamopetalae and monochlamyqae. (15) (4) The classification of Linnaeus was mainly based on Stamens. (25) (4) Ad’, de Candolle first employed the characteristics of vascular tissue in taxonomy. (35) (4) Whittaker placed prokaryotès and akaryotes in Monera. (43) (3) Siphonogama includes Gymnosperm & angiosperm. (49) (2) According to Whittaker kingdom monera includes Prokaryotes & akaryotes. (53) (4) Engler & Prantl classified the Embryophyta on the basis of fertilization. (63) (1) Fertilization by zoodiogamy occurs in Cryptogams. (68) (1) Taxonomy based on all available information and attempting to classify organisms, according to their origin, evolution and variation is called classical taxonomy. A taxonomist engaged in studying origin, evolution, variation and classification of organisms is called classical taxonomist. (69) (2) Hutchinson proposed phylogenetic classification of plants. (70) (3) In five kingdom classification of Whittaker eukaryotes were assigned to only four of the five kingdoni. Prokaryotes are included in kingdom-monera. (71) (4) The present day classification of living organisms is based on anatomical and physiological characteristics (72) (3) The term “phylum” in animal classification was coined by CL. Cuvier,
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(73) (4) Species living in different geographical areas are Allopatric species. (74) (2) Identification is assigning on organism its correct name and placing it in its proper taxonomic category. (75) (3) Sibling species True species which do not interbreed but are otherwise difficult to separate on the basis of morphological characters alone. (76) (4) A true species consists of a population is reproductivity isolated (77) (3) Phenetic classification of organisms is based on observable characteristics of existing organisms (78) (3) Barophillic prokaryotes grow and multiply in very deep marine sediments. (79) (2) Systematics is related with classification of organisms. In classification the organisms are grouped on the basis of .their characters or phylogeny, etc. (80) (2) Acraniata includes marine forms without head or cranium. They lack jaws, vertebral column, paired appendages. (81) (1) Anyone can study, describe, identify and give a name to an organism provide certain rules are followed. This rules are formed and standardised by International Code of Botanical Nomenclature (ICBN) It uses articles, photographs and recommendations (82) (1) Bacterial cell is prokaryotic. It lacks true nucleus, membrane bound organelles and sexual reproduction. (83) (2) Bacteria have different shapes spherical, rod, and spiral are three important type. Cocci may be in cluster or chain form or single and bacilli may be single, in pair in chain. (84) (2) Bacteria utilize the wavelengths longer than 700 nm for photosynthesis and the reaction centre is P-890 the reductant is NADH + Ht In bacteria donor may be H2S or malate or succinate. (85) (3) The Plasmodium often possesses a number of branched ‘veins”. The protoplasm present in the veins show reversible streaming movement. The “veins” disappear and reappear as the Plasmodium moves about. (86) (3) Leishmania donovani causes kala-azar. The parasite is transmitted by sandfly. The parasite lives inside the cells of liver, spleen, lymph glands, white blood corpuscles and inner wall cells of blood capillaries. In sleeping sickness disease, the parasite damages the brain. (87) (3) Mycorrhiza represents mutualistic symbiosis between fungus and roots of higher plants. Fungus helps in absorption of minerals. Water more efficiently and protect plant roots from infection. Fungus also gets food from plant. (88) (3)Aflatoxins, are produced by Aspergillus flavus. Contaminated food is the main source of infection. This toxin causes aflatoxicosis which may lead to haemorrhage and disease of liver.
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ClASSIFICATION Candole classified Plant Kingdom in following two systems (a) Empirical or Pseudo classification. (b) Rational or True classification. (a) Empirical Classification: In this classification only listing of flora is used to identify the plants. The purpose of this classification is to know the flora of surrounding areas. (b) Rational Classification: It is known as true classification, The purpose of this classification is to classify the plants on scientific basis for proper study of subject. This classification is grouped into following three systems. (A) Artificial system
(B) Natural system
(C) Phylogenetic system
(A) Artificial system This system is based on few morphological characters. It is primitive or oldest system of classification. (B) Natural system This system was based on all the possible characters and therefore this system is more useful practically. (C) Phylogenetic system Proposed by ‘Sokel and Sneath”. In it plants are classified on the basis of numbers of similarities and dissimilarties. In this importance to any one character is not given, all characters have same importance. While in natural classification floral (reproductive) characters have more importance than vegetative (root, stem and leaves) characters. Classification By C.B. Von Neil
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ALGAE •
Algae are chlorophyll-bearing, simple, thalloid, autotrophic and largely aquatic (both fresh water and marine) organisms. They occur in a variety of other habitats: moist stones, soils and wood. Some of them also occur in association with fungi (lichen) and animals (e.g., on sloth bear).
•
The form and size of algae is highly variable. The size ranges from the microscopic unicellukr forms like Chiamydotnonas, to colonial forms like Volvox and to the filarnentous forms like Wothrix and Spirogyra. A few of the marine forms such as kelps, form massive plant bodies.
•
The algae reproduce by vegetative, asexual and sexual methods. •
•
Vegetative reproduction is by fragmentation. Each fragment develops into a thallus.
Asexual reproduction is by the production of different types of spores, the most common being the zoospores. They are flagellated (motile) and on germination gives rise to new plants.
•
Sexual reproduction takes place through fusion of two gametes. These gametes can be flagellated and similar in size (as in Chlamydomonas) or non- flagellated (non-motile) but similar iii size (as in Spirogyra). Such reproduction is called isogamous. Fusion of two gametes dissimilar in size, as in some species of Chiamydonionas is termed as anisogamous. Fusion between one large, non-motile (static) female gamete and a smaller, motile male gamete is termed oogamous, e.g., Volvox, Fucus.
•
Algae are useful to man in a variety of ways. At least a half of the total carbon dioxide fixation on earth is carried out by algae through photosynthesis. Being photosynthetic they increase the level of dissolved oxygen in their immediate environment. They are of paramount importance as primary producers of energy-rich compounds which form the basis of the food cycles of all aquatic animals Many species of Porphyra, Linninaria and Sargassum are among the 70 species of marine algae used as food.
•
Certain marine brown and red algae produce large amounts of hydrocolloids (water holding substances), e.g., algin (brown algae) and carrageen (red algae) are used commercially.
•
Agar, one of the commercial products obtained from Gelidium and Gracilaria are used to grow microbes and in preparations of ice-creams and jellies.
60 •
Biology________________________________________________________________________________ Chiorella and Spirullina are unicellular algae, rich in proteins and are used as food supplements even by space travellers.
•
The algae are divided into three main classes: Chlorophyceae, Phaeophyceae and Rhodophyceae.
Common names of Algae:
•
Plants growing on snow or ice are called as aynphytes. Different algal forms produce a specific colour effect while growing as cryophyte e.g., yellow-green by Chiamydomonas yetlowstonensis, red by C. nivalis, black by Scatiella nivalis and purple- brown by Ancyloneina nordenskioldii.
•
Plants growing in hot water are called as thennophytes. Some blue-green algae grow in hot water springs at about 70°C e.g., Oscillatoria brevis.
•
Several algal forms grow on other plants (algae, angiosperms) as epiphytes. e.g., Oedogonium. Cladophora, Vaucheria etc.
•
Some blue-green algae grows as endophytes inside other plants e.g., Anithoena growing inside the leaf of Azofla (fern), Nostoc inside the thallus of An thoceros (hornwort) and Anabaena, Nostoc, Oscillatoria inside the coralloid roots of Cycas.
•
Algae growing on the bodies of animals are described as epizoic. e.g., Cladophora crispata grows on snail shell, Characiurn grows on the antennae of mosquito larvae, Cyanoderma (red alga) and Trichophilus (green alga) are grow on scales of sloth.
•
Algae growing inside the body of animals. e.g., Chlorella grow with in the tissue of Hydra. Some blue-green algae also grow in the respiratory tracts of animals. The blue-green algae which grow endozoically inside the protozoans are called as cyanellae.
•
Some algae like Chlorella, Nostoc etc. growing in symbiotic relationship with members of Ascomycetés and Basidiomycetes (Fungi) constitute the lichen.
61 •
Biology________________________________________________________________________________ The alga Cephaleuros virescens grows a parasite on the tea leaves. In addition, Rhodochytrium, Phyllosiphon are other parasitic algal forms.
•
Several members of algae are unicelled. They may be motile (Chlamydomonas) or non-motile (diatoms). Some forms have a thick wall and become sedentary for certain duration in their life history. They are called as coccoid e.g.. Chlorella, Chirococcus.
•
A colony consists of independent organisms. While the colony of Volvox is motile, that of Hyd rodict you is fixed. A colony having fixed number of cells and division of labour is called as coenobium e.g., Volvox.
•
Most of the algal groups (except blue-green and dthoflagellates) show eukaryotic cell structure. The cell wall is made up of cellulose. Some red algae Corallina) have inpregnation of CaCO3.
•
Some dinoflagellates like Pryninesium, Gymnodinium are extremely poisonous to fishes. The blue-green alga Microcystis secretes hydroxylamine which not only kills aquatic life. While Lyngbya and Chiorella may cause skin allergies in human beings.
•
The red alga Cephaleuros virescens causes-red rust of tea thus destroying the tea leaves. Similar disease are caused by the species of Cephaleuros to coffee plant, Piper and Citrus sp.
•
Algae grow abundantly in water reservoirs where s of nutrients are available to them. This algal Growth floats on the water surface and look like foam or soap lather. It is called water bloom. e.g., microcystis, A nabaena, Oscillatoria etc.
Chlorophyceae •
The members of chlorophyceae are commonly called green algae. The plant body may be unicellular, colonial or filamentous. They are usually grass green due to the dominance of pigments chlorophyll a and b. The pigments are localised in definite chloroplasts. The chloroplasts may be discoid, plate-like, reticulate, cup-shaped,spiral or ribbon-shaped in different species.
•
Most of the members have one or more storage bodies called pyrenoids located in the chloroplasts. Pyrenoids contain protein besides starch. Some algae may store food in the form of oil droplets. Green algae usually have a rigid cell wall made of an inner layer of cellulose and an outer layer of pectose.
•
Vegetative reproduction usually takes place by fragmentation or by formation of different types of spores.
•
Asexual reproduction is by flagellated zoospores produced in zoosporangia.
•
The sexual reproduction shows considerable variation in the type and formation of sex cells and it may be isogamous, anisogamous. or oogamous.
•
Some commonly found green algae are: Chlamydomonas, Volvox, LB at hrix, Spirogyra and Chiv’a.
Spirogyra •
It is an unbranched filamentous green alga of stagnant fresh waters which forms floating masses (supported by bubbles of Oxen) called pond scum. A sheath of mucilage occurs on the outside. It gives a silky touch. Hence Spirogyra is also called water silk or mermaid’s tresses.
•
The thallus is an unbranched and uniseriate filament where cells are arranged in a single row, In some species hold fast is present (e.g., S. fluviatilis). The cells are elongated and cylindrical. The cell wall is two layered the outer is of pectic substance and the inner of cellulose. The outer part (pectin) dissolves in water to form a mucilaginous sheath. Due to this reason Spiro g-yra filament’s are slippery. Transverse or septum can be plane,
62
Biology________________________________________________________________________________ colligate (with H-shaped piece), replicate (ring like ingrowths) and unduliseptate (undulate) The protoplast is differentiated into plasma membrane, thin layer of cytoplasm, single nucleus, one (e.g. S.sahni and S. venkataramanni) or many (16 in S.rectispora) ribbon (spiral) shaped chloroplasts (wavy margin) with pyrenoids and a large central vacuole. Nucleus occurs inside the central vacuole where it is suspended by means of cytoplasmic strands
•
Normally asexual reproduction is absent in Spirogyra. Lt occurs only occasionally by the formation of akinetes, aplanospores and azygospores (Parthenospores).
•
The sexual reproduction in Spirogyra is called conjugation, It involves the fusion of two morphologically identical, but physiologically dissimilar gametes
•
Life cycle in Spirogyra is haplontic as dominant phase in life cycle is haploid (ii) and diploid phase is represented by only zygospore and it undergose R.D. or meiosis (zygotic meiosis).
Utothrix: •
It is a green filamentous algae found in slow running streams. The common species U. wnata occurs in cold water whereas 11. flacca is marine. LI. implexa occurs in esturies (where river meats the sea) as lithophytes.
•
The Ulothrix reproduces vegetatively, asexually as well as sexually.
Phaeophyceae •
The members of phaeophyceae or brown algae are found primarily in marine habitats. They show great variation in size and form. They range from simple branched, filamentous forms (Ectocarpus) to profusely branched forms
63
Biology________________________________________________________________________________ as represented by kelps, which may reach a height of 100 metres. They possess chlorophyll a, c, carotenoids and .xanthophylls.
•
They vary in colour from olive green to various shades of brown depending upon the amount of the xanthophyll pigment fucoxanthin present in them. Food is stored, as complex carbohydrates, which may be in the form of laminarin or mannitol. The vegetative cells have a cellulosic wall usually covered on the outside by a gelatinous coating of algin. The protoplast contains, in addition to plastids, a centrally located vacuole and nucleus. The plant body is usually attached to the substratum by a holdfast, and has a stalk, the stipe and leaf like photosynthetic organ -the frond.
•
Vegetative reproduction takes place by fragmentation.
•
Asexual reproduction in most brown algae is by biflagellate zoospores that are pear-shaped and have two unequal laterally attached flagella.
•
Sexual reproduction may be isogamous, anisogamous or oogamous. Union of gametes may take place in water or within the oogonium (oogamous species). The gametes are pyriform (pear-shaped) and bear two laterally attached flagella.
•
The common forms are Ectocarpus, Dictyota,Laminaria, Sargassum and Fucus
Rhodophyceae: •
Rhodophyta are commonly called red algae because of the predominance of the red pigment, rphycoerythrin in their body. Majority of the red algae are marine with greater concentrations found in the warmer areas. They occur in both well-lighted regions close to the surface of water and also at great depths in oceans where relatively little light penetrates.
•
The red thalli of most of the the red algae are multicellular some of them have complex body organization the food is stored as floridean starch which is very which is similar to amylopectin and glycogen in structure.
•
The red algae usually repro4uce vegetatively by fragmentation.
•
They reproduce asexually by non-motile spores and sexually by non-motile gametes. •
Sexual reproduction is oogamous and accompanied by complex post fertilisation developments.
•
The common members are: Polysiphonia,Porphyra Gracilgsria and Gelidium.
•
Bryophytes include the various mosses and liverworts that are found commonly growing in moist shaded areas in the hills. •
•
Bryophytes are also called amphibians of the plant
kingdom because these plants can live in soil but are dependent on water for sexual reproduction. They usually occur in damp, humid and shaded localities.
•
They play an important role in plant succession on bare rocks/soil. •
The plant body of bryophytes is more differentiated than that of algae. It is thallus-like and prostrate or erect, and attached to the substratum by unicellular or multicellular rhizoids. They lack true roots, stem or leaves. They may possess root-like, leaf-like or stem-like structures.
•
The main plant body of the bryophyte is haploid. It produces gametes, henceis called a gametophyte. The sex organs in bryophytes are multicellular. The male sex organ is called antheridium. They produce biflagellate antherozoids. The female sex organ called archegonium is flask-shaped and produces a single egg. The
64
Biology________________________________________________________________________________ antherozoids are released into water where they come in contact with archegonium. An antherozoid fuses with the egg to produce the zygote. Zygotes do not undergo reduction division immediately. They produce a multicellular body called a sporophyte.
•
The sporophyte is not free-living but attached to the photosynthetic gametophyte and derives nourishment from it. Some cells of the sporophyte undergo reduction division (meiosis) to produce haploid spores. These spores germinate to produce gametophyte.
•
Bryophytes in general are of little economic importance but some mosses provide food for herbaceous mammals, birds and other animals. Species of Sphagnum, a moss, provide peat that have
BRYOPHYTES •
long been used as fuel, and because of their capacity to hold water as packing material for transshipment of living material. Mosses along with lichens are the first organisms to colonise rocks and hence, are of great ecological importance. They decompose rocks making the substrate suitable for the growth of higher plants. Since mosses form
•
dense mats on the soil, they reduce the impact of falling rain and prevent soil erosion.
•
The life cycle of bryophytes consists of two distinct phases — the gametophytic phase and the sporophytic phase. The haploid gametophyte is dominant, long lived, green and independent whereas the diploid sporophyte is short lived and
•
dependent upon the gametophyte. The two phases are morphologically distinct.
•
The gametophytes are either thalloid (i.e., not differentiated into true roots, true stem and true leaves) or leafy shoot having stem-like central axis and leaf-like appendages.
•
The vascular tissue (i.e., xylem and phloem) are completely absent.
•
The bryophytes are fundamentally terrestrial plants but require presence of water to complete their life cycle. The water is needed for dehiscence of antheridia, liberation of antherozoids, transfer of antherozoids from antheridia to archegonia, opening of archegonial neck, and the movement of antherozoids into the archegonial neck.
•
Campbell (1940), Smith (1955), Takhtajan (1953) divided bryophyta into three classes namely Hepaticae, Anthocerotae and Musci. Proskauer (1957) changed the names of these classes in accordance with the recommendations of the code, into Hepaticopsida, Anthocerotopsida and Bryopsida. The latin word Hepatica means liver. Thus the members of hepticopsida are popularly known as liverworts. The members of bryopsida are commonly known as mosses. Liverworts:
•
The liverworts grow usually in moist, shady habitats such as banks of streams, marshy ground, damp soil, bark of trees and deep in the woods.
•
The plant body of a liverwort is thalloid, e.g.,Marchantia. The thallus is dorsiventral and closely appressed to the substrate. The leafy numbers have tiny leaf-like appendages in two rows on the stem-like structures.
•
Asexual reproduction in liverworts takes place by fragmentation of thalli, or by the formation of specialised structures called gemmae (sing. gemma). Gemmae are green, multicellular, asexual buds, which develop in small receptacles called gemma cups located on the thálli. The gemmae become detached from the parent bcxiy and germinate to form new individuals.
65 •
Biology________________________________________________________________________________ During sexual reproduction, male and female sex organs are produced either on the same or on different thalli. The sporophyte is differentiated into a foot seta and capsule. After meiosis, spores ar produced within the capsule. These spores germinate to form free-living gametophytes.
•
Mosses:
•
The predominant stage of the life cycle of a moss is the gametophyte which consists of two stages. The first stage is the protonema stage, which develops directly from a spore. It is a creeping, green, branched and frequently filamentous stage. The second stage is the leafy stage, which develops from the secondary protonema as a lateral bud. They consist of upright, slender axis bearing spirally arranged leaves. They are attached to the soil through multicellular and branched rhizoids. This stage bears the sex organs.
•
Vegetative reproduction in mosses is by fragmentation and budding in the secondary protonema.
•
In sexual reproduction, the sex organs antheridia and archegonia are produced at the apex of the leafy shoots. After fertilisation, the zygote develops into a sporophyte, consisting of a foot, seta and capsule. The sporophyte in mosses is more elaborate than that in liverworts. The capsule contains spores. Spores are formed after meiosis. The mosses have an elaborate mechanism of spore dispersal. Common examples of mosses are Funaria, Pot ytrichum and Sphagnum
Funaria •
Funaria is known as common moss or green moss or cord moss.
•
The main plant body of Funaria is gametophyte and is of two forms. Juvenile form (creeping protonema). Adult form (leafy gametophore)
•
Protonema is the branched filamentous portion which is produced by germination of spores. It is ephemeral or short lived.
•
Leafy gametophore develop from buds produced on protonema and is made up of axis with spirally arranged leaves. I is 1 —3 cm in height green and is monopodially branched. The main branch of leafy gametophore bears male reproductive organs, i.e., antheridia and the side branch is female branch.
66
Biology________________________________________________________________________________
•
Funaria reproduces both by vegetative and sexual methods.
•
Vegetative reproduction : Vegetative reproduction takes place by fragmentation, primary protonema, secondary protonema, bulbils, gemma and apospory.
•
Sexual reproduction The Funaria plants are monoecious and autoecious, i.e., male (antheridia, club shaped) and female (archegonia, flask shaped) reproductive organs are produced on the same plant but on different branches. Male organs mature first and hence Funaria plants are Protandrous.
•
There are two generations in life cycle of Funaria, i.e., gametophytic generation (ii) which is independent and complex and sporophytic generation (2n) which is partially dependent upon gametophytic generation. These two generations follow each other in regular sequence. This is called heteromorphic or heterologous alternation of generations.
Riccia •
The main plant body of Riccia is gametophytic (it). It is small, green, flat and fleshy. The thallus is dorsiventral and dichotomously branched. The thalli are present in the form of patches called rosettes, Scales are found on the margins, while rhizoids are present in the mid-rib region of thallus. Rhizoids are unicellular and unbranched and are of two types — smooth and tuberculate. Rhizoids help in fixation. In submerged species, (e.g., R. fluitans) scales and rhizoids are not present.
• •
Riccia reproduces by both vegetative and sexual method.
Vegetative reproduction Riccia reproduces vegetatively by progressive death and decay, persistent apices (R. diAcolor), adventitious branches (R. fluitans), tubers (R. billardieri, R. discolor, R. perennis) and by rhizoid (R. glauca).
•
Sexual reproduction Sexual reproduction is oogamous type in Riccia. Antheridia and archegonia are the male and female sex organs respectively.
67 •
Biology________________________________________________________________________________ Most of the species are monoecious or homothallic, i.e., male and female sex organs are present on the same thallus. A few species are dioecious or heterothallic, i.e., antheridia and archegonia are present on different thalli. Common dioecious species of Riccia are R.himalayensis and R. frostil.
•
There are 2 generations in life cycle of Riccia. The main plant body is gametophytic (it). The gametophytic phase starts with formation of spores and ends with fertilization. The second phase is sporophytic phase (2n), which starts with zygote and ends with reduction division of spore mother cell. The sporophytic phase is dependent upon gametophyte. Thus there is heteromorphic or heterologous alternation of generations in Riccia. So life cycle in Riccia is diplohaplontic.
PTERIDOPHYTES •
The Pteridophytes include horsetails and ferns.
•
Pteridophytes are used for medicinal purposes and as soil-binders. They are also frequently grown as ornamenta1.
•
Evolutionarily, they are the first terrestrial plants to possess vascular tissues - xylem and phloem.
•
The pteridophytes are found in cool, damp, shady places though some may flourish well in sandy- soil conditions.
•
In pteridophytes, the main plant body is a sporophyte which is differentiated into true root,stem and leaves . These organs possess well- differentiated vascular tissues. The leaves in pteridophyta are small (microphylls) as in Selaginella or large (macrophylls) as in ferns. The sporophytes bear sporangia that are subtended by leaf-like appendages called sporophylls. In some cases sporophylls may form distinct compact structures called strobili or cones (Selaginella, Equiseturn). The sporangia produce spores by meiosis in spore mother cells. The spores germinate to give rise to inconspicuous, small but multicellular, free-living, mostly photosynthetic thalloid gametophytes called prothallus. These gametophytes require cool, damp, shady places to grow. Because of this specific restricted requirement and the need for water for fertilisation, the spread of living pteridophytes is limited and restricted to narrow geographical regions.
•
The gametophytes bear male and female sex organs called antheridia and archegonia, respectively. Water is required for transfer of antherozoids - the male gametes released from the antheridia, to the mouth of archegonium. Fusion of male gamete with the egg present in the archegonium result in the formation of zygote.
•
Zygote thereafter produces a multicellular well- differentiated sporophyte which is the dominant phase of the pteridophytes.
•
In majority of the pteridophytes all the spores are of similar kinds; such plants are called homosporous. Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous. The megaspores and microspores germinate and give rise to female and male gametophytes, respectively. The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos take place within the female gametophytes. This event is a precursor to the seed habit considered an important step in evolution.
•
The pteridophytes are further classified into four classes: Psilopsida (Psiiotum); Lycopsida (Selagineila, Lyco podium), Sphenopsida (Equiseturn) and Pteropsida (Dryopteris, Pteris, ,4dian turn).
Selagineila
68 •
Biology________________________________________________________________________________ Selaginella is commonly called the little club moss or spike moss. Selaginella is mainly found in damp shaded places. The plant body is sporophytic (2n), which is an evergreen and delicate herb having adventitious roots. The plants show great variation in their morphology. Some species are prostrate growing upon the surface (e.g., S.kraussIana), some are suberect (e.g., S. trachyphylla) and others are climbers (e.g., S.allegans). The stem is covered with four rows of small leaves, out of these two rows are of smaller leaves and two o1 large leaves species with dimorphic leaves such as S,kraussiana, S.helvefica, S.lepidophylla, S.chrysocaulos etc.
•
Reproduction takes place by vegetative and sexual (by spores) method.
•
Vegetative reproduction : It is of rare occurrence and may takes place by following methods Fragmentation : It occurs during very humid conditions. Some branches act as adventitious branches, which get separated from the plant and give rise to new Selaginella plants, e.g., in S.rupestris.
•
By resting buds : In some cases, terminal leaves 1 get overlapped and become fleshy and form resting buds, which are means of vegetative reproduction, e.g., in S.chrysocaulos. By tubers In S.chrysorrhizos, some branches penetrate into substratum and at terminal ends swell to form tubers, which give rise to new plants. By apogamy In some cases, development of sporophyte occurs directly from gametophyte without intervention of sex organs, it is called apogamy and such plants are genetically haploid.
•
Sexual reproduction : Tha reproductive structure.jn Selaginella is strobilus or spike. It is a sessile structure and develops at the terminal ends of the branches and its length varies from 114th of an inch to 2—3 inches in different species.
The sporangia are of two types: •
Megasporangia : Borne on megasporophylls. Megasporangium is pale greenish and contains chalky white, yellow or orange megaspores.
The megasporangium is four-lobed structure with a 2-layered jacket, one layer of tapetum and a large number of microspore mother cell. However, only one megaspore mother cell is functional. After meiosis it produces 4 megaspores out of which 1-3 may degenerate. In S.rupestris, there is only a single megaspore.
69 •
Biology________________________________________________________________________________ (ii) Microsporangia : Borne on microsporophylls having a large number of small spores. Thus Selaginella is heterosporous. Microsporangium is pale yellow, oval or spherical body, with 2-layered jacket, one layered tapetum and a number of microspore mother cells which undergo meiosis and form haploid microspores. The main body consists of a wall having two layers, inside which are present numerous small microspores (4002000).
Fern: Ferns live in moist, cool and shady places. They are perennial and evergreen; Fern Dryopteris filixmas is commonly known as Beech fern or Male shield fern or Hay scented fern. •
Fern plant is sporophytic (2n) with an underground rhizomatous stem, large aerial leaves or fronds and adventitious roots. Rhizome is sparingly branched in Dryopteris, moderately branched in Pteris and Adiantum (Adiantum is commonly called “Maiden hair fern” or walking fern because it propagates vegetatively by its leaf tips) and profusely branched in Pteridiurn. The younger leaf is called like a spring from apex downwards are called circinate venation.
•
Younger parts of leaves and rhizome are surrounded by brown hairy structures called scales or ramenta. Leaf bases are persistent.
•
Vegetative reproduction can occur through fragmentation or rhizome and adventitious buds and these on separation gives rise to new fern plant.
•
Sexual reproduction takes place through spores. Spores are born in sporangia. The spores are of one kind only (homosporous). When leaves are mature they bear groups- of son on the under surface of fertile pinnac, Such fronds are called sporophylls.
GYMNOSPERMS
70 •
Biology________________________________________________________________________________ The gymnosperms (gymnos naked, sperma: seeds) are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation. The seeds that develop postfertilisation, are not covered, i.e’, are naked.
•
Gymnosperms include medium-sized trees or tall trees and shrubs.
•
One of the gymnosperms, the giant redwood tree Sequoia is one of the tallest tree species.
•
The roots are generally tap roots. Roots in some genera have fungal association in the form of mycorrhiza (Pinus), while in some others (Cycas) small specialised roots called coralloid roots are associated with N2- fixing cyanobacteria.
•
The stems are unbranched (Cycas) or branched (Pinus, Cedrus). The leaves may be simple or compound. In Cycas the pinnate leaves persist for a few years. The leaves in gymnosperms are well- adapted to withstand extremes of temperature, humidity and wind. In conifers, the needle-like leaves reduce the surface area. Their thick cuticle and sunken stomata also help to reduce water loss.
•
The gymnosperms are heterosporous; they produce haploid microspores and megaspores. The two kinds of spores are produced within sporangia that are borne on sporophylls which are arranged spirally along an axis to form lax or compact strobili or cones.
•
The strobili bearing microsporophylls and rnicrosporangia are called microsporangiate or male strobili. The microspores develop into a male gametophytic generation which is highly reduced and is confined to only a limited number of cells.
•
This reduced gametophyte is called a pollen grain. The development of pollen grains take place within the microsporangia.
•
The cones bearing megasporophylls with ovules or megasporangia are called macrosporangiate or female strobili. The male or female cones or strobili may be borne on the same tree (Pinus) or on different trees (Cycas).
•
The megaspore mother cell is differentiated from one of the cells of the nucellus. The nucellus is protected by envelopes and the composite structure is called an ovule. The ovules are borne on megasporophylls which may be clustered to form the female cones. * The megaspore mother cell divides meiotically to form four megaspores. One of the megaspores enclosed within the megasporangium (nucellus) develops into a multicellular female gametophyte that bears two or more archegonia or female sex organs. The multicellular female gametophyte is also retained within megasporangium.
•
Unlike bryophytes and pteridophytes, in gymnosperms the male and the female gametophytes do not have an independent free- living existence. They remain within the sporangia retained on the sporophytes. The pollen grain is released from the microsporangium. They are carried in air currents and come in contact with the opening of the ovules borne on megasporophylls.
•
The pollen tube carrying the male gametes grows towards archegonia in the ovules and discharge their contents near the mouth of the archegonia. Following fertilisation, zygote develops into an embryo and the ovules into seeds. These seeds are not covered.
•
Gymnospermous wood •
MonoxylIc wood The wood formed may be in one ring due to persistent cambium. Such a wood is called as monoxylic e.g., Pinus.
71 •
Biology________________________________________________________________________________ Cambial activity is short lived, cortex and pith are broad, parenchymatous rays are broad, wood is soft and commercially useless. e.g., Cycas. Pycnoxylic wood The wood is formed in more than one ring due to ephimeral nature of cambium. Such a wood is called as polyxylic.
•
Cambial activity is long lived, cortex and pith are reduced, parenchymatous rays are few, wood is hard and compact, wood is commercially most important and used as good quality timber. e.g., Pinus.
•
The wood of Cedrus deodara is used for making railway sleepers. ft is also used as a structural timber and making bridges. The wood of Qillitris verrucosa, Pin us roxburghii, P. wailichiana, P. pinaster, P. lambertiana etc. is used for making furniture. Juniperus virginiana wood is used for making pencils. The gymnosperm Agathis mist rails is perhaps the largest timber producing tree of the world.
Pinus: •
Pin us is an evergreen, perennial plant of xerophytic nature. Mostly the species are tall and straight. The whorled branching gives a typical conical or excurrent appearance to the plant (due to apical dominance). The plant body is sporophyte and the plants are monoecious. The plant body is differentiated into roots, stem and leaves.
•
Pinus reproduces only by means of spores. Unlike Cycas, here the micro and megasporophylls form compact male and female cone or strobilus respectively.
•
Flints plant is sporophyte (2x), heterosporous (producing two type of spores — microspore and megaspore), monoecious (male and female cones are borne on same plant) and autoecious (male and female cones are borne on different branches). Cycas:
•
Cycas is an evergreen palm-like plant. It is the only genus of family Cycadaceae represented in India.
72
Biology________________________________________________________________________________
•
Cycas plants are dioecious and reproduce by following methods
•
Vegetative propagation : It occurs by means of bulbils (resting adventitious buds) which are produced on the stem in the axil of scale leaves. They break up from the parent plant and germinate to give rise to new plant.
•
Sexual reproduction : Plant of Cycas is sporophyte (2n) and dioecious. The sexual reproduction is of oogamous type, i.e., takes place by the fusion of distinct male and female gametes. The male and female gametes are formed by the germination of micro and megaspores which are born on microsporophylls and megasporophylls. the microsporophylls are grouped together to form a compact conical structure called male cone, whereas the megasporophylls are not aggregated to form a cone, they are produced at the apex of the stem in succession with the leaves.
ANGIOSPERMS •
Unlike the gymnosperms where the ovules are naked, in the angiosperms or flowering plants, the pollen grains and ovules are developed in specialised structures called flowers.
•
In angiosperms, the seeds are enclosed by fruits.
•
The angiosperms are an exceptionally large group of plants occurring in wide rangeof habitats. They range in size from tiny, almost microscopic Wolfia to tall trees of Eucalyptus (over 100 metres).
•
They provide us with food, fodder, fuel, medicines
•
and several other commercially important products.
•
They are divided into two classes : the dicotyledons
•
and the monocotyledons.
•
The dicotyledons are characterised by having two cotyledons in their seeds while the monocolyledons have only one.
•
The male sex organs in a flower is the stamen. Each stamen consists of a slender filament with an anther at the tip. The anthers, following meiosis, produce pollen grains The female sex organs in a flower is the pistil or the carpel. Pistil consists of an ovary enclosing one to many ovules. Within ovules are present highly reduced female gametophytes termed embryo sacs. The embryo-sac formation is preceded by meiosis. Hence, each of the cells of an embryo-sac is haploid. Each embryo-sac has a three-celled egg apparatus - one egg cell and two synergids,
73
Biology________________________________________________________________________________ three antipodal cells and two polar nuclei. The polar nuclei eventually fuse to produce a diploid secondary nucleus.
•
Pollen grain, after dispersal from the anthers, are carried by wind or various other agencies to the stigma of a pisifi. This is termed as pollination. The pollen grains germinate on the stigma and the resulting pollen tubes grow through the tissues of stigma and style and reach the ovule. The pollen tubes enter the embryo-sac where two male gametes are discharged. One of the male gametes fuses with the egg cell to form a zygote (syngamy). The other male gamete fuses with the diploid secondary nucleus to produce the triploid primary endosperm nucleus (PEN). Because of the involvement of two fusions, this event is termed as double fertilisation, an event unique to angiosperms. The zygote develops into an embryo (with one or two cotyledons) and the PEN develops into endosperm which provides nourishment to the developing embryo. The synergids and antipodals degenerate after fertilisation. During these events the ovules develop into seeds and the ovaries develop into fruit.
•
The smallest angiosperm is Woiffia. The plant body of Woiffia consists of tiny flat oval green stem (phylloclade) having a few small roots. The plants are about 1 mm in diameter and found free floating in aquatic habitats like ponds, etc
•
The tallest angiosperm is Eucalyptus. Their trees may attain a height upto 100 meters or more.
•
The plants of Angiosperms is divided into two major groups as — Dicotyledons and Monocotyledons.
(1) Dicotyledons : They are show following distinguished characteristics. •
Tap roots found in the members of this group.
•
The leaves in members of these class exthibit reticulate (net like) venation.
•
The flowers are tetramerous or pentamerous • having four or five members in the various floral whorls, respectively.
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•
The vascular bundles arranged in a ring, numbering 2—6, open and with cambium.
•
The seeds of dicotyledons are with two cotyledons as the name indicate.
(2) Monocotyledons They are show following distinguished characteristics •
Adventitious roots found in the members of this group.
•
The leaves are simple with parallel venation. (iii) The flowers- are trimerous having three members in each floral whorl.
•
The vascular bundles scattered in the ground tissue, many in number, closed and without cambium.
•
The seeds of monocotyledons are with one cotyledons as the name indicate. e.g., Cereals, bamboos, sugarcane, palms, banana, lillies and orchids
* Depending upon the habit of plants, the angiosperms belong to following categories: (1) Herb These are small, soft, non-woody plants without persistent parts above ground. The height of plants usually reaches upto 1 m. The plants may be annual (Brassica), biennial (Sugar beet) or perennial (Canna). The perennial herbs usually possess underground rhizomes which form the new aerial shoots every year. The plants of banana are perennial herbs. (2) Shrubs : These are woody plants of relatively low height (1-4 m). They typically branch at or near the base and do not have a main trunk, e.g., Rose. They are mostly perennial. (3) Trees : These are perennial woody plants with one main trunk. The trunk may or may not be branched. These are of the following types •
Caudex : The stem is unbranched and usually bears a crown of leaves at the apex. e.g., Date-palm.
•
Excurrent : The lower part of stem is thicker which gradually tapers above. Branches arise from the main stem in acropetal succession and plant appears conical e.g., Pinus.
•
Deliquescent The apical bud of the main stem dies after some time and branches and sub-branches spread in different directions. e.g., Tamarindus, Ficus.
(4) Culms : In these plants, nodes and internodes are extremely clear. Internodes of such plants are usually hollow. These plants are grasses but cannot be considered as herb or shrub or tree. e.g., Bambusa (Bans). PLANT LIFE CYCLES AND ALTERNATION OF GENERATIONS In plants, both haploid and diploid cells can divide by mitosis. This ability leads to the formation of different plant bodies - haploid and diploid. The haploid plant body produces gametes by mitosis. This plant body represents a gametophyte. Following ft tilisation the zygote also divides by mitosis to produce a diploid sporophytic plant body. Haploid spores are produced by this plant body by meiosis. These in turn, divide by mitosis to form a haploid plant body once again. Thus, during the life cycle of any sexually reproducing plant, there is an alternation of generations between gamete producing haploid gametophyte and spore producing diploid sporophyte. Different plant groups, as well as individuals representing them, differ in the following patterns: 1. Sporophytic generation is represented only by the one-celled zygote. There are no free-living sporophytes. Meiosis in the zygote results in the formation of haploid spores. The haploid spores divide mitotically and form the gametophyte. The dominant, photosynthetic phase in such plants is the free-living gametophyte. This kind of life
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cycle is termed as haplontic. Many algae such as Volvox, Spirogyra and some species of Chlamydomomas represent this pattern.
Figure : life cycle of Haplontic 2. The type wherein the diploid sporophyte is the dominant, photosynthetic, independent phase of the plant. The gametophytic phase is represented by the single to few-celled haploid garnctophyte. This kind of lifecycle is termed as diplontic. All seed-bearing plants i.e. gymnosperms and angiosperms, follow this pattern.
3. Bryophytes and pteridophytes, interestingly, exhibit an intermediate condition (Haplo-diplontic); both phases are multicellular and often free-living. However, they differ in their dominant phases. A dominant, independent, photosynthetic, thalloid or erect phase is represented by a haploid gametophyte and it alternates with the shortlived multicelluler sporophyte totally or partially dependent on the gametophyte for its anchorage and nutrition. All bryophytes represent this pattern. The diploid sporophyte is represented by a dominant, independent, photosynthetic, vascular plant body. It alternates with multicellular, saprophytic / autotrophic, independent but short- lived haploid gametophyte. Such a pattern is known as haplo-diplontic life cycle. All pteridophytes exhibit this pattern. While most algal genera are haplont-ic, some of them such as Ectocarpus, Polysiphonia, keips are haplodiplontic. Fucus, an alga is diplontic.
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Note •
Differences between Micro & Macrozoospores
Microzoospores
Macrozoospores
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Some Important Antibiotic:
Some common names of fungi
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Divisions of Algae and their Main Characteristics
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EXERCISE-1 1. The yield of paddy can be increased by the application of(1) Nostoc
(2) Symbiotic bacteria
(3) Iron bacteria (4) Archaebac(eria
2. Unicellular cyanobacteria reproduce asexually by(1) Conjugation
(2) Fragmentation
(3) Binary fission (4) Hormogones
3. Red tides are caused by(1) Anabaena
(2) Nostoc
(3) Gleocapsa
(4) Trichodesmium
4. During monsoon ground of becomes slippery because (1) Green algae
(2) Blue-green algae
(3) Mosses
(4) Liverworts
5. Which blue-green alga remain in symbiotic association with Anthoceros — (1) Azolla
(2) Spirochaete
(3) Spirulina
(4) Nostoc
(3) Chiorella
(4) Cladophora
6. Alga associated with Cycas root is — (1) Anabaena
(2) China
7. Some micro-organisms forming nuisance water blooms in lakes, ponds, oceans belong to — (1) Brown and red algae
(2) Desmids and myxomycetes
(3) Cyanobacteria and dinoflagellates
(4) Aquatic angiosperms and algal fungi
8. Which type of ribosomes are found in Nostoc cells— (1) SOS
(2) 60S
(3) 70S
(4) Eukaryotic
(2) Yellow-green alga
(3) Blue-green alga
(4) Red alga
(3) Aulosira
(4) Azospirillum
(3) Green bacteria
(4) Purple bacterium
9. Nostoc is a — (1) Green alga
10. Nitrogen fixers in Azolla is — is also algae (1) Nostoc
(2) Anabaena
11. Which one of the following (1) Cyanobacteria
(2) Rhodospirdlum
12. Heterocyst constitutes — (1) A weakest link in trichome (2) A strongest link in trichome (3) A strong link in some trichomes (4) No link at all 13. In what points the Albugo resemble lllothrix — (1) In food reserves (2) In unicelled gemetangia (3) In cellulosic cell wall (4) In uninucleated cells 14. What holds the conidia together into a chain Cystopus (Albugo) (1) Middle lamila
(2) Cell-wall
(3) Intercalary mucilagenous septum
15. Sexual reproduction by gametangial copulation occurs in
(4) Plamodesmata
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(1) Synchytrium
(2) Yeast
(3) Rhizopus
(4) Both (2) and (3)
(3) llstilago
(4) Colletotrichum
16. Red rot of sugar cane is (1) Puccinia
(2) Albugo
17. ‘LSD is obtained from caused by — (1) Clavatia
(2) Claviceps
(4) Trichoderma
(3) Amanita
18. Fungi are always — (1) Autotrophs
(2) Heterotrophs
(4) Parasites
(3) Saprophytes
19. Yeast is an important source of — (1) Vitamin C
(2) Vitamin B
(3) Vitamin A (4) Vitamin D
20. Pseudomycelium is characteristic feature of — (1) Mushroom
(2) Mucor
(3) Bread mould
(4) Yeast
21. Common form of food stored in a fungal cell is (1) Glycogen
(2) Starch
(3) Glucose
(4) Sucrose
(3) Mesokaryote
(4) Eukaryote
(3) Bacteria
(4) Roots of higher plants
22. Saccharomyces cerevisiae is — (1) Akaryote
(2) Prokaryote
23. Gibberellin was first discovered from — (1) Algae
(2) Fungi
24. In the production of leavened bread, the following is used— (1) Bacterium
(2) Yeast
(3) Rhizopus
(4) None of these
(3)Basidiomycetes
(4) Deuteromycetes
(3) Theophrastus
(4) Bonnier
(3)Aplanospores
(4) Conidia
25. Rhizopus belongs to the class (1) Ascomycetes
(2) Phyeomycetes
26. The term lichen was• first used by (1) Aristotle
(2) Acharius
27. The lichens multiply asexually by forming (1) Chlamydospores
(2) Zoospores
28. The lichens generally do not contain as mycobiont belonging to — (1) Mastigomycotina only
(2) Mastigo and Zygomycotina (3) Deuteromycotina
29. The attachment structures found in lichens (1) Rhizomes
(3) Both of these
(2) Hold fast
(4) Rhizosphere
(2) Lignicoles
(4) Saxicoles
30. Lichens growing on rocks are called — (1) Corticoles
(3) Ter4coles
31. The following lichen is used as food in tundras (1) Cladonia
(2) Parmelia
(4) All of these
(3) Usnea
32. Lichens are important in studies on atmospheric pollution because they — (1) Can also grow in greatly polluted atmosphere (2) Can readily multiply in polluted atmosphere (3) Efficiently purify the atmosphere (4) Are very sensitive to pollutants
(4) All of these
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33. Most of the lichens consist of — (1) Brown algae and higher plant
(2) Red algae and ascomycetes
(3) Blue green algae and acomycetes
(4) Blue green algae and basidiomycetes
34. The symbiotic association of fungi and algae is called — (1) Lichen
(3) Rhizome
(2) Mycorrhiza
(4) Endomycorrhiza
35. Reinder moss is the common name of — (1) Usneacomosa
(2) Cladonia rangiferina
(3) Funaria hygrometrica
(4) Sphagnum aceutifo1ium
36. Bioindicators are — (1) Lichens tracing the presence of pollution (2) Fossil lichens (3) Special type of litmus paper (4) None above 37. Which one of the following is not true about lichens? (1) Their body is composed of both algae and fungal cells (2) These grow very fast at the rate of about 2cm per year (3) Some form food for reindeer in arctic regions (4) Some species can be used as pollution indicators 38. Lichens are ecologically important because (1) Can grow in greatly polluted area (2) They are association of algae and fungi (3) They are pioneers (earliest settlers on barren rocks) and pass xeric conditions successful (4) They are associated with mycorrhiza roots 39. Bryophytes include — (1) Liverworts and ferns (2) Mosses and ferns (3) Mosses and liverworts (4) None of the above 40. Which plant group is known as Amphibians of plant kingdom! ? (1) Pteridophyta
(3) Algae
(2) Bryophyta
(4) Fungi
41. Which commonly known as Peat moss’ or Bog moss’? (1) Polytrichum
(3) Sphagnum (2) Funaria
(4) Riccia
42. Elaters are present in capsule of (1) Riccia
(3) Ant hoceros
(2) Marchantia
(4) Funaria
(3) Anthoceros
(4)Sphagnum
43. Which is commonly known as ‘Hornwort’ (1) Riccia
(2) Marchantia
44. Mosses are indicator of(1) Air pollution
(2) Water pollution
(3) Radiation pollution (4)Soil pollution
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45. In Funaria — (1) Outer peristome teeth are hygroscopic than the inner teeth (2) Both the types of teeth are hygroscopic (3) Inner teeth are responsible for spores dispersal (4) Outer teeth are diploid and inner haplod (2) Riccia (4) Dumottiera bryophytes compared to 46. Elaters are present in sporogonium of — (1) Selaginella (2) Marchantia (3) Riccia (4) Sphagnym 47. A bryophyte differs from pteridophytes in — (1) Archegonia (2) Lack of vascular tissue (3) Swimming antherozoids (4) Independent gametophytes 48. Which among the following was named after the Italian politician P. F. fficci — (1) Funaria (3) Ant hoceros 49. The unique feature of other plant groups is that — (:1) They produce spores (2) They lack vascular tissues (3) They lack roots (4) Their sporophyte is attached to the gametophyte 50. Bryophytes grow in moist and shady environments because — (1) They cannot grow on land (2) Their gametes fuse in water (3) They lack vascular tissue (4) They lack roots and stomata 51. Sporophyte is dependent on gametophyte in (1) Bryophytes (2) Gymnosperms (3) Angiosperms (4) Pteridophytes 52. Among the following which one are non-vascular plants (1) Pieridophytes (2) Bryophytes (3) Angiosperms (4) Gymnosperms 53. Bryophytes are different from fungi in having
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(1) Land habit
(2) Sterile jacket layers
(3) Multiflagellate gametes
(4) Gametophytic plant bàdy
54. Funaria may be differentiated from Pinus by the character (1) No fruits are produced
(2) No seeds are produced
(3) Antheridia and archegonia
(4) Presence of sporophyte 55. The only positive evidence of aquatic ancestry of bryophytes is — (1) Their green colour
(2) Thread-like protonema
(3) Ciliated sperms
(4) Some forms are still aquatic
56. If in Bryophytes like Riccia and Funaria reproduction occurs by parthenogenesis then what will be number of chromosomes in the daughter progeny as compared to its parents — (1) Double
(2) Half
(3) One fourth
(4) Equal to parent
57. An autoecious bryophyte is one in which — (1) Male and female sex organs are produced on the same branch (2) Male and female sex organs are produced on the same plant (3) Male and female sex organs are produced on different plants (4) Male and female sex organs are produced on different branches of the same plant 58. Which among the following is considered advanced among pteridophytes? (1) Club mosses
(2) Ferns
(3) Quillworts
(4) Scouring rushers
59. The rhizophore is not a true root because it is (1) Endogenous
(2) Exogenous
(3) Mesogenous
(4) Endarch
60. The pteridophyte popularly known as ‘Quillwort’ and ‘Merllyns grass’ is — (1) Isoetes
(2) Marsilea
(3) Lyco podium
(4) Selaginella
61. Fern plant is a — (1) Haploid gametophyte (2) Diploid gametophyte (3) Diploid sporophyte (4) Haploid sporophyte 62. A plant having vascular supply, producing spores but lacking seeds is a — (1) Bryophyte
(2) Pteridophyte
(3) Gymnosperm
(4) Angiosperm
63. The first seed plants appeared during which period— (1) Silurian
(2) Devonian
(3) Carboniferous
(4) Cretaceous
64. Seed habit first originated in (1) Certain pteridophytes
(2) Certain pines
(3) Certain monocots
(4) Certain dicots
65. Which of the following plants exhibit independent alternation of generation? (1) Angiosperms
(2) Gymnosperms
(3) Pteridophytes
(4) Bryophytes
66. In which of the following rocks the earlier vascular plants have been discovered ? (I) Early cambrian
(2) Early Devonian
(3) Mid cretaceous (4) Silurian
67. While entering the neck of a fern archegonium sperms show — (1) Phototaxy
(2) Chemotaxy
(3) Thermotaxy
68. Chlorophyll and chloroplast are present in spores of —
(4)Cyclosis
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(1) Lycopodium
(2) Azolla
(3) Dryopteris
(4) Marsillea
69. Which of the following has amphiphloic sipnonostele — (1) Rhizome of Marsilea
(2) Stem of Lyco podium
(3) Rhizome of pteris (4) Stem of Equisetum
70. Heterospory and seed habit are of the discussed in relation to a structure called — (1) Spathe
(2) Bract
(3) Petiole
(4) Ligule
71. ‘Maiden hair fern is — (1) Dryopteris
(2) Azolla
(3) Adiantum
(4) Pteris
72. Sporocarp is a reproductive structure of — (1) Some algae
(2) Some aquatic ferns having son
(3) Angiosperms having spores
(4) Bryophytes
73. Protostele is — (1) Stele divided into many parts (2) Early stele with central solid xylem surrounded by phloem (3) Latent stele (4) Angiosperm stele 74. Polystelic condition is found in (1) Rachis of Pteris (2) Roots of Dryopteris (3) Stem of all species of Selaginella (4) Stem of Selaginella willdenowii 5. The vasèular supply given from the main stele for leaf is called — (1) Leaf gap
(2) Leaf trace
(3) Branch trace
(4) Haplostele
(2) Moss
(4) Fern
76. lndusium is found in — (1) Fungi
(3) Algae
77. The walking fern is so named because (1) Its spores are able to walk (2) It is dispersed through the agency of walking animals (3) It propagates vegetatively by its leaf Ups (4) It knows how to walk by itself 78. Prothallus means — (1) Immature gametophyte (2) Immature sporophyte (3) Immature archegonium (4) None of these 79. Which one of the following is the earliest land plant? (1) Cordaites (2) Cooksonia
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(3) Hornea (4) Rhynia 80. Neck canal cells are absent in archegonia of — (1) Bryophytes (2) Gymnosperms (3) Pteridbphules (4) All of these 81. The ovules of Gymnosperms are — (1) Anatropous and Unitegmic (2) Orthotropous and Unitegmic (3) Anatropous and Bitegmic (4) Orthotropous and Bitegmic 82. Resin canals and Mucilage canal of Gymnosperms are example of(1) Schizogenous cavity(2) Lysigenous cavity (3) Large vacuole (4) Inter cellular cavity 83. Birbal Sahni discovered fossil plant ‘Pentaxylon from Rajmahal hills of Bihar belongs to(1) Bryophyta (2) Pteridophyta (3) Gymnosperm (4) Angiosperm 84. Endosperm in Gymnosperm is formed — (1) At the time of fertilization (2) Before fertilization (3) After fertilization (4) Along with the deyelopment of embryo 85. In Gymnosperm, Endosperm is formed by — (1) Fusion between a male gamete and two polar nuclei (2) Fusion between a male gamete and a polar nuclei (3) Fusion between egg and male gamete (4) Germination of megaspore 86. The endosperm of Gymnosperm is(1) Haploid
(2) Diploid
(3) Triploid (4) Tetraploid
87. Fruits are not formed in Gymnosperms because of — (1) Absence of pollination
(2) Absence of seed
(3) Absence of fertilization
(4) Absence of ovary
88. The phenomenon of vivipàry has been observed in which Gymnosperm (1) Agathis alba (2) Pinus walichiana
(3) Ephedra trifurcata (4) Cycas cercinalis
89. Xylem element of Gymnosperm lacks(1) Vessels (2) Tracheids
(3) Parenchyma (4) Scierenchyma
90. Phloem element of Gymnosperm lacks — (1) Sieve element (2) Companion cell
(3) Parenchyma (4) Sclenchyma
91. Non-porous wood is the characteristic feature (1) Gymnosperm (2) Angiosperm
(3) Both 1 and 2 (4) None of these
92. Archegonia are absent in the ovules of —
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(1) Cnetum (2) Welwestchia
(3) Ephedra (4) Both 1 and 2
93. Vessels are present in the wood of — (1) Cycas, Pinus, Ephedra (2) Ephedra, Pirnis, Gnetum (3) Ephedra, Gnetum, Weiwestchia (4) Ephedra, Weiwestehia, Thuja 94. Bitegmic ovules are found in(1) Gnetum and Welwestchia (2) Gnetum and Ephedra (3) Ephedra and Weiwestehia (4) Wejwestchia and Araucaria. 95. The longest neck of archegonia is found in which of the Gymnosperm — (1) Gnetum
(2) Ephedra
(3) Welwestchia (4) Pinus
96. Polycotyledonary habit is found in — (1) Monocot
(2) Dicot
(3) Ferns (4) Gymnosperm
97. In which of the following, fertilization is possible without water — (1) Algae
(2) Brypnytes
(4) Gymnosperm
(3) Pteridophytes
98. In Gymnosperms, the vascular strand is made up of ? — (1) Conjoint vascular bundles (2) Open vascular bundles (3) Collateral vascular bundles (4) All of the above 99. In Gymnosperms, the seeds are naked because they lack(1) Integuments
(2) Pericarp
(3) Nucellus
(4) Parienth
100. In Gymnosperms, seeds are said to be naked because they— (1) Do not have ovule
(2) Do not have ovary
(3) Do not contain endosperm
(4) Do not contain starch
101. Cones and flowers are similar because (1) Both are bright and showy (2) Both are reproductive organs (3) Do not contain endosperm (4) Do not contain starch 102. The embryo sac in a angiosperm is a — (1) Megasporangium (2) Megaspore mother cell (3) Megagametophyte (4) Megaspore 103. Fertilization in which male gametes are carried through pollen tube is called —
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(1) Porogamy
(2) Syngamy
(3) Siphonogamy
(4) Chalazogamy
104. When pollen of a flower is transferred to the stigma of another flower of the same plant, this pollination is referred to as — (1) Xenogamy
(2) Geitonogamy
(4) Allogamy
(3) Autogamy
105. An embryo may sometimes develop from a cell of embryo sac other than egg, this is called — (1) Parthenocarpy
(2) Apogamy
(3) Apospory
(4) Parthenogenesis
(2) Anucleate
(3) Multinucleate
(4) Dikaryotic
106. The tapetal cells are — (1) Uninucleate
107. If sporophyte of sporophytic plant contain 16 chromosomes, then no. of chromosomes in a microspore mother cell will be — (1) 16
(2) 8
(3) 32
(4) 24
108. Development of sporophyte without fertilization from the vegetative cells of the gametophyte is called — (1) Zygospory
(2) Aplanospory
(3) Aposporv
(4) Apogarny
109. In angiosperms, a. mature male gametophyte is derived from a pollen mother cell by — (1) Three mitotic divisions (2) One meiotic and two mitotic divisions (4) A single meiotic division (3) Two meiotic divisions 110. Aleurone layer helps in(1) Protection
(3) Nutrition
(2) Growth
(4) Water absorption
(3) Coconut
(4) All of these
111. Nucellar polyembryony is seen in (1) Citrus
(2) Zea
112. Growth of pollen tube towards embryo sac is(1) Chemotropism
(2) Thigmotroptsm
(3) Geotropism
(4) None of these
113. Poisonous pollens are in(1) Alnus
(2) Citrus
(4) Seania
(3) Putranjiva
(4) Integument
(3) Nucellus
114, Perisperm is remaining part of — (1) Endosperm
(2) Ovule
115. Formation of plant from the ovum is called(1) Apospory
(2) Apogamy
(3) Amphimixis
(4) Parthenogenesis
116. A totipotent cell means(1) An undifferentiated cell capable of developing into a system or entire plant (2) An undifferentiated cell capable of developing into an organ (3) An undifferentiated cell capable of developing into complete embryo (4) Cell which lacks the capability to differentiate into an organ or system 117. Parasexual hydridisation means fusion of — (1) Male gamete with female gamete (2) Male gamete with synergid
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(3) Somatic protoplasts (4) Male gamete with somatic cell 118. Hundreds of antipodals cells are found in — (1) Bambusa
(2) Sasa
(3) Gossypium
(4) None of these
119. Germpore is the region where exine is — (1) Thick
(2) Uniform
(3) Thick and uniform
(4) Absent
120. Tapetum is found in(1) Anther (2) Male gametophyte (3) Female gametophyte (4) Microspore 121. When pollen tube enters through faniculus or integument, it is called — (1) Porogamy
(2) Chalazogamy
(3) Mesogamy
(4) Isogamy
(3) Nucellus
(4) Embryo
122. Exalbuminous seeds store food in(1) Endc5sperm
(2) Cotyledons
123. The role of double fertilization in angiosperms is to produce(1) Endosperm
(2) Integuments
(4) Endocarp anther
(3) Cotyledons
124. If there are 4 cells in be the, what will number of pollen grains — (1)8
(2)4
(3) 16
(4) 12
125. If the cells of root in wheat plant have 42 chromosomes, then the no. of chromosome in the cell of pollen grain is — (1) 14
(2) 21
(3) 28
(4) 42
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EXERCISE-2 I. Give the answer of following questions in one or two lines. (a) Nocticula is colourless & does not have chloroplast and it has holozoic mode of nutrition. But yet they are placed in dinoflagellates. (b) What is the reason that some dinoflagallates (e.g. Nocticula and Pyrosystis) show ‘Bioluminescence (c) Dinoflagellates are called mesokaryote, why? (d) Why, diatoms are used as a heat insulator”, (e) Why Oscillatoria can surrive in hot water streams. 2. Give the answer of following questions in one or two lines. (a) How we can consider that green algae are similar to higher plant. (b) Why Sargassum, Laminaria etc. algae having brown colour. (c) Which type of algae form coral reefs and why? (d) Why Thallophytes do not have embryo? (e) Why bread becomes soft & spongy when yeast cells are added in wheat dough. 3. Give the answer of following questions in one or two lines. (a) “Noctiluca is the Protist of Pyrophyta division and the zygotic meiosis present in the organism of pyrophyta division but absent in Noctiluca” write the reason of above statement. (b) Why diatoms are not destroyed as quickly as other algae (c) In the basis of classification floral character are comparatively more used than vegetative character. Why? (d) Why diatoms soil used for insulation of boilers and vapour pipes? (e) Why the good yield of rice is obtained without using nitrogenous fertilizer for many years? 4. Give the answer of following questions in one or two lines. (a) Why the Pteridophytes are more adaptive terrestrial plant as compare to Bryophytes ? (b) What is the reason that Bryophytes, prefer to grow in moist . shady places. (c) Why the life cycle of Gymnosperm is diplontic. (d) If the spice between inner cell wall and cell membrane has been blocked in gram negative bacteria. What effect will be observed. (e) Why the Linnaeus’s classification syStem also known as sexual system. 5. Answer the following questions in one word. (a) Write the name of that brown algae which is the source of iodine. (b) Write the name of that portist which is known as the connecting link between animals and plants and having holophytic and saprophytic mode of nutrition. (c) Write the name of that fungi, which is also known as Baker’s yeast. (d) Write down the name of fungi, which is also known as weed of laboratory. (e) Which fungi is responsible for “powdery mildew of pea” (f) Write the name of that green algae which lives on tea plant as a parasite and produce “red rust” diseases on it. (g) Write down the name of saprophytic moss
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plant. (h) Write down the name of the smallest Pteridophyte plant. (i) Write down the name of aquatic Pteridophyte plant in which secondary growth will be find in stem. (j) Write down the name of Gymnosperm plant which is also known as “maiden hair tree” 6. Answer the following questions in one word. (a) Which type of life cycle is found in Bryophytes? (b) Those scientific name in which generic name and scientific name both are similar, known as? (c) Those species which are morphologicaily similar but reproductively isolated are known as? (d) “All the members that can interbreed among themselves and can produce fertile off spring are the member of same species.” The given definition is according to which scientist. (e) Write down the name of the scientist who classify the plants, on the basis of vascular tissue in non-vascular and vascular group. (f) A group of genus which shows the general structural similarities in floral organs from one another in known as? (g) A person who studied about the origin, evolution, variations and classification of plants, is known as? (h) Write the name of that symbiotic relationship which is present between the roots of seed plants and fungi. (i) In an aquatic environment microscopic animals and plants are collectively known as (j) A motile, flagellate asexual cell is known as 7, Match the column-I with Column-II.
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11. Correct the mistakes in the given paragraphs (a) The structure of blue-green algae is similar to Gram postive eubacteria. Its cell wall is also bilayered. Outer wall is made up of lipoic acid) and inner wall is made up of cellulose: The cell memebrane of BGA is made up to chitin.The cytoplasm of BGA is divided in to two parts. The peripheral cywplasm is known as hyaloplasm and central cytoplams is known as centroplasm. (b) Some blue green algae can perform nitrogen fixation. They convert atmospheric oxigen in a nitrogenous compounds like amino acid. A special type of cell is found for niotrogen fixation in the blue green algae which is known as cyst . This special type of cell contains ribozyme enzyme for nitrogen fixation. For the synthesis of this enzyme there is a special type of gene present in this special cell which is known as Huf gene. Blue green algae perform nitrogen fixation both saprophytically and asymbiotically. 12. Correct the mistkes in the given paragraph. Cell wail of prokaryotes is made up to peptidoglycan. It’s structure has two parts. (i) lipids (ii) amino acids. But exceptionally cell wall of Acetobacter xylenum is made up of protein. Those prokaryotes which are inter-cellular lack cell wall. Cell membrane of prokaryotes is made up of lipoprotein. The space between cell wall and cell membrane known as periplastidial space This space is analogus to golgibody because in this space digestion of simplex substance is done. Prokaryotes also lack the true chromosome. Instead of it a false chromose is present, which is made up of as circular naked DNA, small amount of RNA and histone protein. In prokaryotes cell wall invaginets which results in formation of kind of structure, called as microsome. It structurally similar to mitochondria. 13. Correct the mistakes in the given paragraph. On the basis of vascular tissue Oswald Tippo classified the plant kingdom in two sub kingdom. Thallophyta and Embryophyta. Oswald Tipp classfied the sub kingdom Thallophyta in ten divisions Cyanophyta, Euglenophyta, Zoodiophyta, Chrysophyta, Pyrrophyta, Phaeophyta, Rhodophyta, Shizomycophyta, Myxomycophyta and Rhizomycophyta. On the basis of embryo sub kingdom Embryophyta classified in two divisons Atracheata and Tracheophyta. Division Atracheata classified in three classes Hepaticopsida, Psilopsida and Bryopsida. Class Hepaticopsida include Hornworts and class bryopsida includes Liverworts. Division Tracheophyta classified in four classes Psilopsida, Anthoceropsida, Sphenopsida and Pteropsida. Class psilopsida includes Ferns and Pteropsida includes Psilotum, Gymnosperm and Angiosperm. 14. In the following lines write the suitable word in place of underlined words. (a) Members of some species inhabiting similar environment and having some genetic variations are known as Ecotvpe. (b) Those species found in similar geographical regions are known as svnchronic species. (c) The dynamic concept of species was proposed by Linnaeus. According to this concept species is always changeable.
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(d) Typological concept of species was proposed by Aristotle and Robert. (e) Those species which are found in different geographical regions and have geographical barrier between them are known as svmpatric species. (f) Plants growing in a particular area known as fauna. (g) If any scientist, write the flora of a particular area then he used Rational classification. (h) The classification of any plants or animals in written in ascending order. (i) All the humans in this world can inter breeding among themselves, so all the humans are the members of many biological species. (j) Genus is smallest taxonomic category and basic unit of classification. 15. In the given paragraph fill in the blanks The cell wall of diatoms is made up of (1)……………. in which silica particles are embedded in at many places. Due to which the cell wall appears to be made up of silica. This sillicated cell wall is called “shell’ or……. (2)………. Their cell wall is made up of two halves, which are arranged like the lids of a soap box. These half parts are collectively known as …….(3)…………… In this part which is present on the upper side acts as lid and, the known as………. (4) ……….and the other basal part is known as……………(5)……The place where there two parts over laps each other is called ……..(6)…………..In the cytoplasm of diatom……… present, in which a………….(8)……… nucleus is present. Their cells have chloroplast, in which chlorophyll ‘a’ chlorophyll c and……….. (9)………….. pigments are present In this storage food is…………. (10)………..and fats.(oil). 16. In the given paragraph fill in the blanks — The main plant in bryophyte is……….. (1)……….sex organs are……… (2) ………and jacketed in bryophytes. Male sex organs are called as………… (3)………… and female sex organs are called as………. (4)…….. The male gametes of bryophytes are motile. These motile male gametes are called as…….. (5)……… In bryophytes, fertilization is done by……….(6)………. As a result of fertilization, a diploid……… (7)……. is formed. In bryophytes structure formed after the fertilization is developed by……….. (8)……. divisions. During development 1st & IInd division are…….. (9)……….. But second division is right angle to the first divisions which r suits. In formation of a 4-celled embryo. Now the third division in 4-celled embryo is………. (10)……. which results in formation of 8-celled embryo. 17. Fill in the blanks (Rhizoides, Key, Basidiocarp, Basidium, Taxon, Heirarchy, Allochronic species, syncihronic species, Gymnosperm, Herbarium, museum, Azolla, chlorella,Sori, monocotyledonae, ;icotyledonae) (a)The……… are root like structures which help in anchorage and absorption of water in the bryophytes. (b) The phanerogams are seed bearing plants and are divided into………………….. and angiosperm. (c) A scheme for identification of plants and animals is known as a……………….. (d) The fruiting body containing basidium is multicellular structure called………………… (e) Descending arrangment of taxonomic categories is known as……………………. (f) Those species found in different time periods are known as………………….. (g) The collection or depository of dried plant specimen is known as………………… (h) If………………… is grown with rice, than the production increases up to 50%. (i) The yellow or brown spots which have sporangia in fern are called……………..
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(j) Trimerous condition of floral whorls is characteristic of…………………………. 18. Fill in the blanks (a) When the determination of species is based on interbreeding then it is called •as…………….. (b) Similarities and dissimilarities in structures of protein help to know the……………. of living being. (c) Bacterial cell wall can be dissolved by…………………………… enzyme. (d) Proteins present in the cell wall of gram negative bacteria are called………………………….. (e) Cells, carrying coP factor secrete the………………… which have an antibiotic effect on other microbes. (f) Endospore is highly resistant structure due to presence of……………………….. in its wall. (g) The process of water conduction is bryophytes take place with the help of……………………… (h) Blue green algae is surrounded by a mucilagenous sheath. This sheath is made up to………………. (i) The cytoplasm of prokaryotes lacks membrane bound cell organelles but exceptionally in klue green algae two membrane bound structue are present. (i) Gas vacuole (ii)………………………. (j) According to two kingdom system blue-green algae was included in class……………………. of algae. 19. Read the given paragraph caretully and answer the following questions. Do you believe in fairlies? whether do or not, you must believe in ‘fairy rings’ for they are being seen very often in meadows. There you would find a ring of grass much brighter arid richer and after a wet day in summer you may see a ring of toadstools too. If you were to dig up a toadstool you would find a mass of fine white threads. The toadstool is a fungus and these threads constitute the chief part of the plant. There is no green part, so the toadstools cannot make food as green plants do. It consists of a rounded cap, smooth and white above but bearing a large number of brown gills below. The spores grow like a fine powder on the sides of the gills. (a) The mushroom is (i) A plant consisting of fine green threads (ii) An edible fungus (iii) A flowering plant (iv) A bryophyte devoid of root: stem and leaf; (b) Reproduction in fairy rings occurs by means of — (i) Seeds (ii) Spores (iii) Flowers (iv) All of these Cc) The toadstools and mushrooms usually appear— (I) In the water logged soil (ii) During winter season (iii) In summer after rains (iv) In autumn (d) The brown gills of mushrooms (1) Have no function to perform (ii) Are meant for its respiration
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(iii) 1-laif the plants to float in water after heavy rains (iv) Bear spores which help in reproduction (e) Toadstools cannot manufacture their own food because (i) They do not have roots (ii) They do not have leaves (iii) They do not have chlorophyll (iv) They do not need food for their growth
Directions for (Q.20-Q.27) : Each questions contain STATEMENT-I (Assertion) and STATEMENT-2 (Reason). Each question has 4 choices (1), (2), (3) and (4) out of which ONLY ONE is correct.
(1) Statement- 1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement -1 (2) Statement -1 is True, Statement -2 is True Statement-2 is NOT a correct explanation for Statement - 1 (3) Statement - I is True, Statement- 2 is False (4) Statement -1 is False, Statement -2 is False 20. Statement 1 : Only red algae are able to flourish at the great depth of sea. Statement 2 : Red algae has the pigments r-phycoerythrin and r-phycocyanin. 21. Statment 1 : Spirogyra shows anisogamy. Statement 2 : Gametes are identified on the basis of their motility. 22. Statement 1 : Chiorella could be utilised to keep the air in space vehicles. Statement 2: The space travellers feed on Chiorefla soup. 23. Statement 1 Zygospore of U?othrix forms meiozoospores and meioaplanospores. Statement 2 : Both are motile, 24.Statement 1 : Bryophytes possess archegonium as a female sex organ. Statement 2 : Algae also possess the archegonium. 25. Statement 1 : Sporogonium of Riccia is totally dependent on the gametophyte. Statement 2: Sporogonium of Marchantia is partly dependent on the gametophyte. 26. Statement 1 Sporophytes of pteridophyta are dominant individual. Statement 2 : They do not show the formation of true root. 27. Statement 1 : Gymnosperms seeds are naked. Statement 2 : They lack ovary wall.
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EXERCISE-I 4. (2). During monsoon ground becomes slippery because of blue-green algae. 15. (3). Sexual reproduction by gametangial copulation occurs in Rhizopus. 20. (4). Pseudomycelium is characteristic feature of yeast. 27. (4). The lichens multiply asexually by forming Conidia. 30. (4). Lichens growing on rocks are called Saxicoles. 34. (1). The symbiotic association of fungi and algae is called Lichen. 44. (1). Mosses are indicator of air pollution. (53) (2). Bryophytes are different from fungi in having Sterile jacket layers. (59) (2). The rhizophore is not a true root because it is Exogenous. (61) (3). Fern plant is a Diploid sporophyte. (67) (2). While entering the neck of a fern archegonium, sperms show Chemotaxy. (71) (3). Maiden hair fern’ is Adiantum. (75) (2). The vascular supply given from the main stele for leaf is called Leaf trace. (82) (2). Resin canals and Mucilage canal of Gymnosperms are example of Lysigenous cavity. (84) (2). Endosperm in Gymnosperm is formed before fertilization. (87) (4). Fruits are not formed in Gymnosperms because of absence of ovary.
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(96) (4). Polycotyledonary habit is fouiid in Gymnosperm. (100) (2). In Gymnosperms, seeds are said to be naked because they do not have ovary. (104) (2). When pollen of a fidwer is transferred to the stigma of another flower of, the same plant, this pollination is referred to as Geitonogamy (108) (4). Development of s5orophyte without fertilization from the vegetative cells of the gametophyte is called Apogarny. (115) (4). Formation of plant from the ovum is called Parthenogenesis. (123) (1). The role of double fertilization in angiosperms is to produce Endosperm.
EXERCISE-I (1) (a) Becuse Nocticula has two flagella and plated cell wall is also present in it. (b) Because in some dinoflagellates protoplasm have photogenic granule. These granule made up of luciferin protcin. Energy is released by the oxidation of luciferin. This energy is liberated in the form of light during night. So they show bioluminescence. (c) Because histone protein is absent in its chromosome,.:. due to this reason dinoflagellates are called mesokaryotes. (d) Because the wall of diatom is bad conductor of heat and it is made up of silica. (e) Oscillatoria can surrive in hot water streams, due to the presence of homopolar bonds in proteins and having complex cell wall. (2) (a) On the basis of following points we can consider that green algae similar to higher plants. (i) Pigment (chlorophyll a, chlorophyll b and Carotenoiods) (ii) Stored food ( Starch) (iii) Cell wall (made up of cellulose and pection) (b) The amount of fucoxanthin (brown coloured pigment) is more in brown algae, due to which these algae is brown in colour. (c) Red algae. Because some red algae secret calcium carbonate and deposite on their walls, thus these algae forms coral reefs. (d) Because in thallophytes sexual reproduction takes place through zygotic meiosis, due to this reason embryo is absent in thallophytes. (e) Because in the fermentation process CO2 is produced by which bread becomes soft and spongy. (3) (a) Because diploid nucleus in present in Noctiluca. (b) Because silica is present in diatoms cell well. (c) Because floral character are more conservative than vegetative character. (d) Because the well of Diatoms in made up of silica and it is bad conductor of heat. (e) Because nitrogen fixing blue green algae are found in paddy fields. (4) (a) Because vascular tissue and roots are present in Pteriodophytes.
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(b) Bryophytes prefer to grow in moist and shady places because their male gametes (antherozoites) are motile so, it needed water for fertilization. (c) Gymetophyte of Gymnosperm is reduced and short lived so that sporophytic generation is dominant in gymnospem, due to this reason life cycle is diplontic. (d) The complex substances will not be digested. (e) Because he classify on the basis of reproductive organs (stamen and style)
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(16) (1) Gametophyte/Haploid (6) Zoodiogamy (7) Zygote
(2) Multi-cellular (3) Antheridia (8) Mistosis/Mitotic division
(17) (a) Rhizoides (b) Gymnosperm
(c) Key (d) Basidiocarp
(g) Herbarium (h) Azolla
(i) Son (j) monocotyledonae
(18) (a) Biological species
(b) Phylogenetic relationship
(e) Colicins
(f) Ca-dipicolinate
(g) Parenchyma
(4) Archegonia (5) Antherozoites
(9) Vertical/longitudinal
(10) Transverse
(e) Heirarchy (f) Allochronic species
(c) Lysozyme
(d) Porins
(h) Mucopolysaccharide/Pectic acid
(i) Thylakoids (j) Cyanophyceae or myxophyceae (19) (A) (ii), (B) (ii), (C) (iii), (D) (iv), (E) (iii) (20) (1).The red algae fluorish and occur in abundance at great depths of sea where other plants do not occur in abundance. The sunlight as it penetrates water, portions of spectrum such as red, orange, yellow and green light rays which are of short wavelengths are filtered out. Only the blue and violet rays of great wavelength remain and penetrate to great depths. The green pigment chlorophyll cannot trap these light rays of great wavelength and the green plants are thus unable to carry on photosynthesis at these depth. On the other hand the red pigment y - phycoerythrin and a blue pigment y — phycocyanin which are characteristic pigments of all the red algae, can utilize wavelengths of light (blue and violet rays) not absorbed by chlorophyll. (21) (2). In Spirogyra, the fusing gametes are morphologically alike but dissimilar in their behaviour. One of the fusing pairs may be more active than the other. The gametes of Spirogyra are distinguishable by their degree of motility. This different in behavior is the first step towards anisogamy. It is called physiological anisogarny. (22) (2). Chiorefla could be utilised to keep the air in space vehicles pure and supply food in space stations and prolonged space flight trips. The space travellers could feed on Chiorella soup. It is nourishing but not appetizing food. (23) (3). The zygospore of Ulothrix, on germination, does not directly develop into a new filament. Instead its nucleus undergoes zygotic meiosis. The resultant four haploid daughter nuclei are organised into meiospores which may be motile (meiozoospores) or non-motile (meioaplanospres). (24) (3). The female sex organ of the bryophytes is a remarkable structure. It appears for the first time in the liverworts and mosses and continues in the pteridophytes. Archegonium is absent in thallophytes (algae and fungi). Sex organs in them are male gametes and female gamete. (25) (2). Sporogonium of Riccia completely lacks chloroplasts. Therefore, it is dependent upon the gametophyte for food, water and minerals. However in Marchantia, with differentiation of the young sporophyte into foot, seta and capsule, the immature cells of the seta, capsule walL elaters and even those of the foot develop chlorophyll. They are autotrophic to a considerable extent. It may be partly dependent upon the parent plant (gametophyte) for its food supply. For the supply of water and minerals in solutions it is entirely dependent upon the parent plant. (26) (3). In the pteridophytes, the sporophyte gains physiological independence and develops into the dominant, typically photosynthetic phase of the life cycle. It is organized into stem, leaves and roots. For the first time in the sporophyte of the pteridophytes true roots develops. Psilophyta (a pteridophyte division) lack true roots. (27) (1). The gymnosperms have their ovules freely exposed before and after fertilization. They are not enclosed by any ovary wall. The seeds formed by them lack seed coat. Hence due to absence of every wall and seed coat their seeds are nacked.
