Question

If there are $20$ centromeres in a cell at the mitotic anaphase, then how many chromosomes are there in each daughter cell following cytokinesis?

• A. $20$
• B. $10$
• C. $30$
• D. $40$

Answer 1

Answer: (B)

$10$

Before separation sister chromatids remain attached at centromeres. After separation each chromatid becomes a daughter chromosome.

The cell is still dividing and not separated in two daughter cells by cytokinesis. If there are 20 centromeres seen in anaphase, then there are 20 chromosomes in the dividing cell.

Thus each pole of the dividing cell will receive 10 chromatids: each chromatid will now become a chromosome for daughter cell.
Thus each daughter cell, immediately after cytokinesis will have 10 chromosomes, each made up of single chromatid.

Hence, answer is '10 chromosomes'.