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Cell Cycle and Cell Division
<~a): . > 3-4 n * Rudolf virchow Cisss) L» _ Pre-existing cell __ce, New Cell C2 parent cell) division (2 daughter cel) Ly Life of oll demuatly Seproducing organism stave w/ a Single cab = called > zoaotee ’ \ divisions Mmulticeliar matwre body / organtam diyisto orma”* organiom burt i Om © ae Cs 4 Characteristics of coll Ctrve r iving o¢ gms to Vnestore. @ ——> (@) Nucleo-
95/7. Awriatzon => Phase blw Luo uecessive M- tw CefL Cycle = | Intevphase| + | M-phase QA {s) Go starts w/ ends wi phase of Nuclear Cytop larmic ONA division division (o-ordinated replica” A 02 uo ecific_phase ) Kar yo Kinesis tokinesis “eo ? f P corresvond to 9 Cell Growth Cin terms of chromoscenaer Cytoplasmic) —> cont. process (G1/5/1G2) tophe Metap A phase » Tepe ese 3 Gd Phase ?- m Longest Phase; dedsion Yor ces division - Metabo Weally active t grow continuously. Cmax. wrouth) _t, No DNA rep lica® ro" Most of vorganellar -dupLication mitochondria, chloroplast, golgi body — q+) * centriole duplican -s b> Nucleoside, Nucleotide, DNA POL Cnreyme, ATP synsneris o> Protein Synthesis [rtistone protein ~ S ] *Tobwhin _protetn — G2 #* $ Phase :- + ON ication is in Nucleus LONA Pol. active ) ) Histone protein sythests ts cnrometin __ clupuica — i0le “ Cin onunat cell) (2¢— Uc) > In $s phase , Amount of ONA oluplic otes But, Chromosome No. seman same Can — 2n) fayentcell | Cu S Qa M (2 daughter cet) | Amoont oF 2c 2 WC ac] 2c ONA a. Chromosome no. ——— S~ He > i <, v ® F eee ——— oom 4 3, No. oF chromatids | 3 1} 2 pe chromosome NCERT Summary ?- ei: e iodon and hase mMosomMe, ated 4 a L i chromatid chromosome GA phase. ~ + Mitochondria» chloroplast » Golgi body duplicates — oe Tubviin pr Ofeim forme” ier . y r prepara" o - 4 A OLiON, onk --- Cc & Aome Kells ear 1 division by eg. Heart Celt ___* Netve Celh re Sern ; (| Difserenriated = > (mutt iply) (cca nur Cell death | Secondary grow hy of- plants } | & + replace ost cell r -or jsatio Virtu, all components of cell oceur, “Almost md kar yo lei nesis ——?_Gtokinesis - j ressiv rocess. > No wtleay out Mines b/w _P /M/A/ Telophase ® MITOSIS. progeny uO) © 69: ONA = AC 2c 2c chromosome No.: 2n = Y 2n=4 2n= 4 > Equationabl ~division parent * progeny ccetl. OF porentcele + qt 9 S_ > G2 —> Prapnase > Metaphone pNA= ac 2c 4c 4c T] Propnase o> longest phase of karyokinesis Trick : Pappy —> _Prophase Con > « Inikiodion of condensa” of chromoseme) materiat C chromatin ) ¢ chromatin n > Chromosome — condensed / coil) wntongle ° om, chvemosome. + Foch chrosome has wo auster chromatids (a held _tagether at _centromere, 2)—>+ Centrosomes_Ccentriole duplicated in Sphase) Move tow ards opp- poles + form Apindte sible. => rati > Disoppesrance of Nuceolus, ER GB ete Salo. > Apindle apparatus | mitotic apparatus jotmation, = S TI Anapnare. > Shortest phase of Katuyyorinedts Sister eneeratids vane seonidentd os —-dlaughtey: Chromosomes OF —_-puture daughter : beach 4 chromatid y UPNALKEC manna \) ( 4 \\) i \) () INA = 4c 4C Chr. No. = an=4 an=4 an=8 Chromatid., a 4 per_chr. Chromatid n.- 8 g 8 (fot-) TY ‘Telophase _ > Dpp. 64 prophase 4) Chromosome yeacy Chromatin, jespettive poles ° decondenses * Tongle . | idenctit * Cnromosomey elong ation (SS LV, 3.) Repprma™ oh nuclear _ Pnwelope (from RER > DNA = UC ch. = 2n=8 © simivon to panends — te $n pome _ Organisms , << n> (O90 ©—1— ©) —1— Go) karyokines{s karyokinesis Not followed _ Not followed by cytokinesis “4, ta tokinesis ™’ Mel hifi ry eg. Liquid endosperm of Coconut © (al Growth _~» Disturb “Nucleo-eytoplasmue rorio L Cell divides _festores Hus Jodo 1.) Growth un -mmuticeNutar organisms cLEpidermis) 2.) in Cells 0 er L of ski Is oF lini cells Blood Cells 3) Mitosis in Meristem in Plants (Apical and Lateral > or 5 v * continvovS growth _+hrovghovt life In vanimar cells :- Mitosis occurs ino diploid. Somatic _cells. mM exception: 6” hon orl, t mibesis Sper n)-> In Plants -- Mitosis occurs in _ both _haptoid. ONd.diploid_cells a_i mi hb bmo cells, *(olchicine [ Mitotic Imnibitor ] » Alkaloid fun plant Colchicum pytumnale Cliliacea family) + 9t_ inhibits dpinddle fibre formation It arrest «cell .olivision in Metaphase Mitotic inhibitor 9b induces polyp Loidig, dime _-pLardiet Qn —t > 4n colchicine > romo ° s is 0 Chromosomes. ¢ In diploid organisms eg dn= 46 Can) yr_asister chromotidy oo —_ — * Paternal Maternal 1 BB- black 1 chromosome 1 othe chromosome 4 1 bb” blue 1 Y 8 t 1 (black) chu —(sts—s—“—s;istC Gene CDNA) v mRNA ; 1 ; io ' ' 1 ; 1 ' Pro lem u - Phacocter. ceprens. BivalenE : 4 pain ef homologous chromosornen AD ADA y ¢ L 1 Bivalent F ol chromosomes 4 Kinetochores~ ¢ CHomolog006) [ 2 centromeres 4 chromatid alsokla TETRAD <——— Bivalent = Tettad “ frilis > Seek aut ation TT eabsent_ thread / spindle fibre No chromatin condensahon » No chromosome -formation > No spindle +ormation ©—+— @©—_—— cS ( = Cell constric™ dhaped constriction nudes =(Karyokinesic) followed by _=(Cytokinesis) crevi t Payqmoeciuun Amitosis = Binary Fission b>» (mode voy { Seprodyc’) Uimode of cell otivision) PYG 2IF: DNA replica” in barterya —_occors sin + Ans.= priory to fission * After Meiosis I > Chromosome » Reductional division i > tS Eayationar dAivisio nm t= m DNA amount half Ob compared -to parent cell __ty Reduetional Aviston. % Meiosis involves 2 Arquentiol cycles of Nudear On aeth division division But ion ocev one ~Longer $# more complex than Prophase .of Mitsis __ chromosomal _ he haviour tene 4) Leptotene = Early Prapnase 1 + Compaction Of chromosomes continues throughout __Leptotene. * Chromosime becomes gradually visible in Light microscope ‘long, thin slendey hnomosomes. (om ~~ ‘Called Bovquet sta quet ie @ 4 1). Nuclear envelope ad b) Zygotene. * later pairing 64 homologous chromosomes, called Synapse. foe \ * Synaptonenra Complex formed ve, «Bivalent —-_- Or Tetrad Formed >(Clearly visible in Pachy iene) 4) Pachytene ‘Longer than _eptotene # zugotene —_—. “Chrometids dsindly wisible ae e TETRADeheonly wAuble me $s & *ecomblnase enzym € _siner™ Sister ids ___Ltrossing over | Genenelic Non- sister Recombination chromatids maker b/w wnon- Sister chromatid of homologous chr. n At Recombina® ==Noduke Csite OF recombine) 
