Q. The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testis is :
(a) Spermatogonia → spermatid → spermatocyte → sperm
(b) Spermatocyte → spermatogonia → spermatid → sperms
(c) Spermatogonia → spermatocyte → spermatid → sperms
(d) Spermatid → spermatocyte → spermatogonia → sperms
Solution :
Correct option : C In human males, the primordial germ cells divide mitotically and produce spermatogonia. Some of the spermatogonia grow into large primary spermatocytes. Each primary spermatocyte undergoes first maturation. division which is a reductional (meiotic) one. Thus, the primary spermatocyte divides into two haploid daughter cells called secondary spermatocytes. Each secondary spermatocyte now undergoes second maturation division which is a mitotic one. Thus, each secondary spermatocyte gives rise to two spermatids that undergo transformation to form two sperms. Overall, two secondary spermatocytes give rise to four sperms. So, the correct answer is ‘spermatogonia → spermatocyte → spermatid → sperms’.
