the m phase
Post on 27-May-2015
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Cytokinesis, The M-Phase
M-Phase
What is M-Phase?
M-phase or mitotic phase occurd after interphase stage, the dividing cells enter M
phase
M-Phase
Has two major parts Mitosis Cytokinesis
Can subdivided into 4 phase
Prophase
Metaphase
Anaphase
Telophase
Prophase• The chormosomes in the nucleus condense
and become more tightly coiled• Each chormosomes consists a pair of sister
chormatids joined together at the centromere.• The spindle fibre in the cytoplasm begin to
form and extends between the centrioles.• The nucleolus disappers and the nuclear
membrane diseintegrates at the end of prophase
Metaphase
• Begin when centromeres of all the choromosomes are lined up on the metaphase plate.
• Two sister chromatids are attached to one another at the centrometer.
• Metaphase ends when the centromeres divide.
Anaphase
• Two sister chormatids of each chromosomes separate at the centromere.
• The sister chromatids are pulled apart to the opposite poles by shortening of the spindle fibre .
• The separated chromatids are called daughter chromosomes.
• The two sister chromatids of each chromosome separate at the centromere
• Spindle fibres will contract and pull apart the sister chromatids to the opposite poles
• Once separate, the chromatids are referred to as daughter chromosomes
Telophase
• Begins when two set of chromosomes reach the opposite poles of the cell.
• Chromosomes start to uncoil and revert to their extended state.
• The spindle fibre disappear and a new nuclear membrane form around each set of chromosomes.
• The nucleolus re-form in each nucleas.
So what is Cytokinesis?
1)Following mitosis, the cytoplasm of the cell will divide through a process called cytokinesis to form two daughter cells, each having one nucleus2) Cytokinesis is the process of cytoplasmic division3) It usually begins before nuclear division is complete THAT IS CYTOKINESIS
Cytokinesis in animal cell
• Actin filaments in the cytoplasm started to contracts to pull a ring of the plasma membrane,forming a cleavge furrow.
• The cleavge furrow deepens progressively until the cell is separated into two daughter cell.
Cleavage furrow
16Sia Lily
Is the cytokinesis in animal cell is same as the plant cell?
Cytokinesis in plant cell
• A clevage furrow does not form.• Instead a membrane –enclosed vesicles gather at the
plant cell’s equator between the two nuclei.• The vesicles fuse to form cell plate.• The cell plate grow outward and fuse with plasma
membrane of the parent cell.• New cell wall and plasma membrane are formed from
the content of the cell plate• Cellulose fibre are produced at the end of cytokinesis.
The End
Me Gusta!!
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