CELL DIVISION Nageli coined the term cell division

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 CELL DIVISION (क श क व भ जन ) • Nageli – coined

CELL DIVISION (क श क व भ जन ) • Nageli – coined the term cell division (क श क व भ जन ) - ‘each cell arise from pre existing cell’ for plant cell • Flimming– observed cell division in animal cell (amitosis) and named it direct division जत क श क ओ म सतर व भ जन क ख ज डबलय फलम ग न क | • Sterberger - observed cell division in plant cell सट रसबरगर न सतर व भ जन क सरवपरथम क श क ओ म अधययन क य प दप • Farmer and Moore – coined the term meosis अरधदसतर व भ जन मर न क क ख ज सरवपरथम • Robert Remark – coined the term amitosis 1905 म फ रमर एव

S phase or synthesis phase S अवसथ • DNA amount become double (2 c

S phase or synthesis phase S अवसथ • DNA amount become double (2 c to 4 c) • Centrosome replication • Histone protein formation • Chromosomes become double (2 sister cromatids from the single cromatid of each chromosome is form) • ड एनए क म तर द गन ह (2 स स 4 स ( ह ज त • Centrosome replecation • ह सट न • कर म स म पर ट न क न रम ण डबल ह ज त ह

G 2 phase/ Pre mitotic division/ 2 nd growth phase /2 nd gap phase

G 2 phase/ Pre mitotic division/ 2 nd growth phase /2 nd gap phase G 2 अवसथ • Synthesis of • (a) RNA- for coiling and condensation of DNA • (b) Protein • Tubulin (for formation of SF) • Cinase (transfer cell from G 2 to M phase, division of cell organel like mitochondria & chloroplast, nucleus grows in size) • सशलषण • )ए) ड एनए क जम व और सघनन क ल ए आरएनए • )b) पर ट न - • टयब ल न (एसएफ क गठन क ल ए ( • क इनज (G 2स M चरण म सल क सथ न तरण , म इट क नडर य और कल र पल सट जस क श क अग क व भ जन , क श क कदर य

Prophase परव वसथ Late prophase • Nuclear membrane and nucleolus completely disappear so chromosome

Prophase परव वसथ Late prophase • Nuclear membrane and nucleolus completely disappear so chromosome come in direct contact with nucleo-cytoplasm • Each chromosome contains 2 sister chromatids • At the end of the prophase each centrosome reaches the opposite poles. व लव त परव वसथ • कदरक वरण नषट ह ज त ह। • त र कदर (Centriole) क व भ जन ह ज त ह और एक दसर स दर ह त ज त ह द न सटर स म एक दसर स अध क स अध क दर पर वय स भ मख (diametrically opposite)

Metaphase मधय वसथ • Shortest and thickest chromosome can be seen • Irregularly present

Metaphase मधय वसथ • Shortest and thickest chromosome can be seen • Irregularly present chromosome, now arrange in a regular manner at the center of the cell known as equatorial plate/ metaphasic plate. This process is known as congression. • सबस छ ट और सबस म ट कदरकसतर दख ज सकत ह • कदरकसतर तरक क मधयरख क समतल

Anaphase पशच वसथ • Most active and shortest phase • Due to shortening of

Anaphase पशच वसथ • Most active and shortest phase • Due to shortening of spindle fiber, centromere divides into two and each chromosomes divides into 2 chromatids or daughter chromosomes. • Shape of chromosomes can be studied in anaphase • At the end of this phase chromosomes reaches the opposite poles. Polar/continuous spindal fiber Interzonal SF Chromosomal/ discontinuous SF • पशच वसथ म परतयक कदरकसतर क द न भ ग एक दसर स पथक ह न लगत ह तथ इs अवसथ क अत क ल तक अभ मखकदर तक पहच ज त ह।

Telophase अतय वसथ • Despiralization –chromosome forms chromatin net • Nuclear membrane and nucleolus

Telophase अतय वसथ • Despiralization –chromosome forms chromatin net • Nuclear membrane and nucleolus reappear • Final result of telophase is formation of 2 daughter nuclei • इस अवसथ म कदरकसतर समह और कदर क च र उतपनन ह त ह। क द न ओर कदर वरण

ज इग ट न Zygotene • Homologous chromosomes being to pair • Synaptonemal complex

ज इग ट न Zygotene • Homologous chromosomes being to pair • Synaptonemal complex also develops during this stage • ज इग ट न उप वसथ यगमन ह त ह। म गणसतर क

पच ट न Pachytene • Each chromosome of the diard splits into 2 parts

पच ट न Pachytene • Each chromosome of the diard splits into 2 parts in all its length except centromere and form tetrad chromatid. This structure is known as chromatid • Exchange of chromatid segment between non sister chromatid of homologues chromosomes pair is called as crossing over. Crossing over • पच ट न – कर स ग ओवर ह न |

ड पल ट न Diplotene • Both chromosome of homologues chromosomes pair move away

ड पल ट न Diplotene • Both chromosome of homologues chromosomes pair move away from each other (due to electrostatic forces). But they are attached at the point where crossing over has taken place, this point is called chiasmata • Due to continuous repultion between homologous chromosome all the chiasmata present between them move towards the terminal part. Chiasmata • ड पल ट न – ड पल ट न अरधदगणसतर टकड़ टटर वलनट सथ त म कय जमट क आद न – परद न म ( पर ह त ह | (

ड ईक इनस स Diakinesis • Movement of chiasmata on the chromosome is known

ड ईक इनस स Diakinesis • Movement of chiasmata on the chromosome is known as terminalization • In this stage neuclear membrane and nucleolous completely disappear • In this stage centrosome has already reached upto the opposite pole of the cell • कनदरक कल एव कदर क नषट ह ज त एव

Anaphase I एन फज परथम • Due to shortening of SF homologues chromosomal pair

Anaphase I एन फज परथम • Due to shortening of SF homologues chromosomal pair move towards the pole. This process is known as disjunction or reduction phase. • Haploid no. of chromosome have reached upto the opposite pole • इसम गणसतर व पर त धरव क ओर ज त ह |

Telophase I ट ल फज परथम • Despirelization of chromosome • Daughter nuclei form

Telophase I ट ल फज परथम • Despirelization of chromosome • Daughter nuclei form • Half no. of chromosome • Double the amount of DNA • ट ल फज कदर क परथम म कनदरक सपषट ह ज त कल एव तथ गणसतर

Cytokinesis II क श क दरवय व भ जन दव त (स ईट क

Cytokinesis II क श क दरवय व भ जन दव त (स ईट क ईनस स • Plant cell- cell plate formation • Animal cell- Groove formation दव त )

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