stages of mitosis with explanation
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Answer:
Today, mitosis is understood to involve five phases, based on the physical state of the chromosomes and spindle. These phases are prophase, prometaphase, metaphase, anaphase, and telophase.
Answer:
The answer is
Explanation:
Mitosis consists of four basic phases: prophase, metaphase, anaphase, and telophase.
i.Prophase:- It is the first visible stage in karyokinesis. The chromosomes appear as long coiled threads called chromatids. The chromatin becomes shorter, thicker and visible due to the condensation of DNA.
ii. Metaphase:-
Nuclear membrane and nucleolus completely disappears and simultaneously appearance of spindle fibres. Spindle fibres are attached to the centromere of a chromosome. The chromosomes are arranged on the equatorial plane. The process of gathering of chromosomes in equator is called congression and plate formed is called metaphasic plate.
iii. Anaphase:-
The centromere of each chromosome splits into two sister chromatids and forms two daughter chromosomes. The daughter chromosomes are pulled towards the poles due to the contraction of spindle fibres and stretching of interzonal fibres. During polar movement, the chromosomes show different shapes i.e. J, U, V, L or I shaped in appearance. At the end of anaphase, each pole will get one set of daughter chromosomes. It is the shortest phase and is also known as a migratory phase.
iv. Telophase:- The daughter chromosomes reach respective poles and uncoil and become thin, long and visible. The spindle fibres start disappearing and finally disappear. The nuclear membrane and the nucleolus reappear.
Two nuclei are formed at the end of telophase. Both the nuclei have the same number of chromosome as the parent cell. It is the last visible stage of karyokinesis and is also known as reorganization phase.
It is followed by cytokines or division of cytoplasm.