Question

Assertion (A): During anaphase, centromere of each chromosomes splits and chromatids separate.

Reason (R): Chromatids move to opposite poles.

Options

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true but R is not the correct explanation of A.

• A is true but R is false.

• A is false but R is true.

Answer 1

Both A and R are true but R is not the correct explanation of A.

Explanation:

The assertion is true because anaphase begins precisely with the simultaneous splitting of each chromosome's centromere, which releases the paired sister chromatids into independent units. The reason is also true because these newly separated sister chromatids are immediately pulled toward opposite poles of the cell by contracting spindle fibres. However, this is not the correct explanation of the assertion; the movement of the chromatids is a consequence of the centromere splitting, rather than the cause of it.