Question

The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testis is

• A. spermatogonia $\to$ spermatocyte $\to$ spermatid $\to$ sperms
• B. spermatid $\to$ spermatocyte $\to$ spermatogonia $\to$ sperms
• C. spermatogonia $\to$ spermatid $\to$ spermatocyte $\to$ sperms
• D. spermatocyte $\to$ spermatogonia $\to$ spermatid $\to$ sperms

Answer 1

Answer: (A)

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.