Question

$2n=16$ in a primary spermatocyte which is in metaphase of first meiotic division. What shall be the total number of chromatids in each of the secondary spermatocyte?

• A. 32
• B. 8
• C. 16
• D. 24

Answer 1

Answer: (C)

16

Spermatogonium (2N) divides by mitosis and we get primary spermatocyte (2N) and by meiosis from one primary spermatocyte (2N), we get two secondary spermatocytes (N).
Now, the number of chromosomes present in secondary spermatocyte is N and in one chromosome, there are two sister chromatids.
So, if there are 16 chromosomes in primary spermatocyte, the secondary spermatocyte will have half the number i.e.; 8 chromsomes and the chromatids will be 8*2 = 16.
Thus, the correct answer is '16'.