Biology Review Sheet for Cell Unti

Biology Review Sheet Chapter 4 Test Timeline: 1665: Robert Hooke observes dead cork cells. They are dead plant cells and he looks as the cell wall.

1673: Anton Von Leeuwenhoek is Leeuwenhoek is the first to observe living cells. He calls them animalcules. 1880s: The Cell Theory THE CELL THEORY states that… 1. All liv living ing thi things ngs are mad madee of cell cellss 2. Cel Cells ls come come onl only y from from oth other er cell cellss 3. Cells are are the basic basic unit unit of struct structure ure and functi function on in all all living living things things Schleiden: plants are made of cells Schwann: animals are made of cells Virchow: cells come from other cells Cell Diversity - Cells come in different shapes and sizes - The function of a cell determines its size and shape - The human body contains 200 different types of cells - BLOOD CELLS: carry 02 and food throughout the body - NERVE CELLS: send and transmit electrical impulses/messages - SKIN CELLS: are protection and a barrier 

Internal Organization

PROKARYOTIC - no nucleus - no membrane - bound or organelles EUKARYOTIC - we humans - nucleus present - organ ganelles present Cell Membrane -

phos phosph phol oliipid pid bila bilay yer  regul regulat ates es wha whatt ente enters rs and exit exitss the the cell cell phos phosph phat atee head head and and fat fatty ty acid acid tai taill head head is is hydr hydroph ophil ilic ic mean meanin ing g wate waterr lovi loving ng

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tail is hydrophobic meaning water fearing bilayer is so that the tail can be away from water and the head can be near the water  membrane proteins help large molecules to cross the membrane A. Integral Protein: goes from one side through to the other side B. Peripheral Protein: on the surface and they don’t go all the way through the membrane. fluid mosaic model means many different components

Nucleus

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contains the genetic information for the cell “nuclear envelope” surrounds the nucleus “nucleolus” is the site where the ribosomes are made “chromatin” is where DNA and proteins will condense and become chromosomes “nuclear pores” allow the ribsomes and RNA to leave the nucleus

Mitochondria

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site of chemical reactions and cellular respiration located in muscle and nerve cells especially because of their high energy requirement two membranes A. Outer: lines the mitochondria B. Inner: cristae increase the surface area so more reactions can occur  has its own DNA called MDNA (mitochondrial DNA)

Ribosomes

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site of protein synthesis most numerous organelle no membrane two types A. Free Ribosomes: produce proteins that stay in the cell B. Attached Ribosomes: (to E.R.) produce proteins that will be exported from the cell

Endoplasmic Reticulum - intracellular highway - system of membranes/tubules - moves substances within the cell - two types A. Rough E.R. - covered with ribosomes - makes proteins that leave cell - digestive enzymes and anitbodies

Golgi Apparatus -

B. Smooth E.R. no ribosomes assembles lipid molecules produces Calcium ~ muscle contraction liver/kidneys and filters toxins

flattened, membranous sacs receives, packages, and transports the proteins cis face = receives trans face = sends

Vesicles

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small, spherical organelles that contain proteins classified by their content A. Lysosome: contains digestive enzymes 1. Phagocytosis: digestion of food particles 2. Autophagy: recycling organelles 3. Autolysis: destruction of cell B. Food Vacuole: stores food C. Contractile Vacuole: pumps water out of cells

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filaments and tubes found in the cytoplasm give shape and support to the cell two structures 1. Microtubules - hollow tubes made of protein (tubulin) - used in cell division (spindle fibers) - used to move chromosomes 2. Microfilaments - thread-like structure made of protein (Actin) - help cell movement - help muscle contraction

Cytoskeleton

Cilia and Flagella - Made of microtubules - 2 types - Both have the same cross section - Nine pairs of microtubules that surround one central pair  1. Cilia - small, short, numerous hair-like structures - used for movement (Paramecium) - Respiratory Tract: filters and moves organisms 2. Flagella - used for locomotion

- sperm! - fewer, longer, whiplike motion, propel Cell Wall

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only located in PLANT CELLS gives shape and support, rigid, made of a chain of cellulose pores/openings in the cell wall that allow particles to move in and out of the cell o A. Primary: develops first, just outside of cell membrane o B. Secondary: forms when primary reaches maximum size, can’t grow anymore

Central Vacuole - fluid-filled organelle - filled with water  - used for storage, wastes, and toxins Plastids

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storage organelles double membrane own DNA (circular DNA) 1. Chloroplasts: 2. Chromoplasts: store pigments (red, orange, yellow). Carotenes is orange 3. Leucoplasts: store starch (potato)