Question

How many sperms and ova will be formed from 100 secondary spermatocytes and 100 secondary oocytes respectively?

• A. 400 and 100
• B. 100 and 100
• C. 400 and 200
• D. 200 and 100

Answer 1

The correct option is D 200 and 100

Spermatogenesis is the formation of sperms in males and oogenesis is the formation of ova in females after they reach. Both processes occur under the influence of follicle-stimulating hormone. In spermatogenesis, one primary spermatocyte (46 chromosomes) undergoes meiosis I to form two secondary spermatocytes (23 chromosomes). These two secondary spermatocytes undergo meiosis II to form four spermatids (23 chromosomes) which mature into sperms. If 2 secondary spermatocytes form 4 sperms. So, 100 secondary spermatocytes will form 200 sperms.

In oogenesis, one primary oocyte (46 chromosomes) undergoes meiosis I to form one secondary oocyte (23 chromosomes) and the other first polar body (23 chromosomes) which has very little cytoplasm. The secondary oocyte undergoes meiosis II to form the ova (23 chromosomes) and second polar body. So overall one secondary oocyte forms one ova.
Therefore, 100 secondary oocytes will form 100 ova.