Question

Which of the following is the correct statement about spermatogenesis?

• A. Spermatogonia have 46 chromosomes and always undergo meiotic cell division.
• B. Primary spermatocytes divide by mitosis.
• C. Secondary spermatocytes have 23 chromosomes and undergo second meiotic division
• D. Spermatozoa are transformed into spermatids.

Answer 1

Answer: (C)

Spermatogenesis is the formation of sperms that takes place in seminiferous tubules. It begins with growth phase of germ cells i.e. spermatogonia. These cells are formed in yolk sac and are transferred to testes. Spermatogonia being germ cells have 46 chromosomes and these undergo mitosis and growth to form primary spermatocytes. These then undergo meiosis-I to form secondary spermatocytes which then undergo meiosis-II to form spermatids. These spermatids then transform into spermatozoa and then sperms. Primary spermatocytes are formed due to mitosis and hence contain 46 chromosomes while secondary spermatocytes have 23 chromosomes.