Structure of cells and organelles Prokaryotic cells Major differences between prokaryotic and eukaryotic cells Prokaryotic cells (bacteria, cynobacteria) Eukaryotic cells (green plants, fungi, animals) Usual sually ly extr extrem emel ely y sm small, all, 0.5 0.5--10µm 10µm in diam diamet eter er Usual sually ly lar larger cel cells, 1010-10 100 0 µm µm in in diam diamet eter er Mostly binary fission, no spindle Mitosis, meiosis, or bot! spindle formed.
"#$ is circular circular and lies free in te cytoplasm (no true nucleus). "#$ is na%ed (not associated istone proteins or $ to form cromosomes) n some pro%aryotes, sexual system inoles transfer of some "#$ from one cell to anoter
"#$ is linear and contained in a nucleus. "#$ is associated 'it istone proteins and $ to form cromosomes *exual system inoles complete nuclear fusion bet'een special sex cells (gametes), 'it e+ual contribution from bot nuclei ell 'alls present, but cemically c emically different from tose ell 'alls present in plants and fungi! tey made of of plants! tey contain polysaccarides and amino cellulose or citin acids (peptidoglycans) e' organelles! membraneous structures absent or Many organelles, bounded by double membranes ery simple and existing briefly in te cell (cloroplasts, mitocondria, nucleus) and single membrane (olgi apparatus, lysosome, acuole, endoplasmic reticulum) /rot /rotei ein n synt synte essised ised in small all ribo ribossomes omes (0*) 0*) /rot /rotei ein n synt synte esi sise sed d in lar large ribos bosomes omes (0*) 0*) *ome cells ae simple flagella! tese are 'itout *ome cells ae complex cilia and flagella! tese ae microtubules, 20 nm in diameter 342 arrangement of microtubules, 200 nm in diameter *ome *ome can fix nitrog nitrogen en for for use use in amino amino acid acid synt syntesi esiss #one #one ae ae tis tis faci facilit lity y Differences between plant and animal cells /$#6 7* 6oug, 6oug, sligtly elastic cellulose cell 'all present (in addition to te cell membrane) /its /its and and pla plasm smod odes esma mata ta pres presen entt in in te te cell cell 'all 'all Midd Middle le lame lamell llaa 8oi 8oin n cel celll 'al 'alls ls of ad8a ad8ace cent nt cell cellss
/lastids, e.g. cloroplast and leucoplasts, present in large numbers Mature cells normally ae a large single, central acuole filled 'it cell sap 6onoplast present around acuole ytoplasm normally confined to a tin layer at te edge of t cell #ucleus at edge of te cell ysosomes not normally present entrioles absent in iger plants ilia and flagella absent in iger plants *tarc grains used for storage :nly nly mer meris iste tem matic atic cel cells are are cap capab ablle of of di diiision sion e' secretions are produced
$#M$ 7* ell 'all absent-only a membrane surrounds te cell #o cell cell 'all 'all and and te tere refo fore re no pits pits or plas plasmo mode desm smat ataa Midd Middle le lam lamella ella abse absent nt-c -cel ells ls are are 8oi 8oine ned d by by int inter erce cell llul ular ar cement /lastids absent 9acuoles, 9acuoles, e.g. contractile co ntractile acuoles, if present, are a re small and scattered trougout te cell 6onoplast absent ytoplasm present trougout te cell #ucleus any'ere in te cell but often central ysosomes almost al'ays present entrioles present ilia or flagella often present lycogen granules used for storage $lm $lmost ost al all cel cellls are are capa capabl blee of of di diiision sion $ 'ide ariety of secretions are produced
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