Biology
Enumerate the various changes that occur in the nucleus of the cell during (a) prophase (b) anaphase of mitotic division.
Cell Division
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Answer
(a) Prophase
- Centrioles start moving apart and reach opposite poles.
- Chromosomes become distinct.
- Chromosomes are already duplicated as paired chromatids.
- Sister chromatids attached to each other at a small region called centromere.
- Spindle fibres appear between daughter centrioles forming the achromatic spindle.
- Nuclear membrane and nucleolus disappear.
(b) Anaphase
- Centromere attaching the two chromatids divides/splits.
- The two sister chromatids of each chromosome separate and are drawn apart towards opposite poles pulled by shortening of spindle fibres.
- A furrow starts in the cell membrane at the middle in animal cell.
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