Question

Describe cytokinesis in Plant and Animal cells.

What are the purposes of mitosis?

Answer 1

Cytokinesis is a process of cytoplasmic division into two daughters cells.

In plant cell :- During interphase ,golgi apparatus accumulate enzymes ,structural proteins and reminents of Endoplasmic reticulum and mitochondria are dispersing throughout the cell.During telophase these vesicles and cell organelle reminents transported on microtubules to form a phargmoplast( a vesicular structure) at metaphasic plate.There these vesicles fuse and coalesce from the centre towards the edges of cell wall ( centrifugal method ) .This method of cytokinesis is known as cell plate method.

In Animal cell :- In animal cell ,they lack cell wall .A contractile ring composed of actin filaments forms just inside the plasma membrane.Actin filaments pulls the equator of cell inward ,forming a fissure .This fissure is know as cleavage furrow .furrow will forms from edges of cell towards the centre of cell at the cell equator( Centripetal method ) .As actin filaments ring contracts furrow becomes more deepen, eventually the parent cell divided into two daughter cells.

Purpose of mitosis :- mitosis is known as equational division

1) mitosis results in formation of 2 daughter cells ,these are similar to parent cell as well as each other.

2) In mitosis number of chromosomes remain same in parent cell and daughter cells.

3) All somatic cells show mitosis.To replace old , worn-out cells,help in growth also .