Question

Describe the process of spermatogenesis in brief. Add a note on the role of FSH and LH in spermatogenesis.

Hint:

Remember: Spermatogenesis = Spermatogonia → Spermatocytes → Spermatids → Spermatozoa. Controlled by FSH (Sertoli cells) and LH (Leydig cells → testosterone).

Answer 1

Definition: Spermatogenesis is the process of formation of haploid male gametes (sperms) from diploid spermatogonial cells in the testes. It occurs in the seminiferous tubules of testes. 

Steps of Spermatogenesis: \[\begin{array}{rl} 1. & \text{Multiplication phase: Spermatogonia (diploid, 2n) undergo repeated mitotic divisions to increase their number.} \\ 2. & \text{Growth phase: Some spermatogonia enlarge to form primary spermatocytes (2n).} \\ 3. & \text{Meiotic phase: - Primary spermatocytes undergo meiosis I to form two haploid secondary spermatocytes (n). - Each secondary spermatocyte undergoes meiosis II to form two spermatids (n).} \\ 4. & \text{Spermiogenesis: Spermatids differentiate and transform into mature, motile spermatozoa (sperms).} \\ \end{array}\]

Role of Hormones: \[\begin{array}{rl} \bullet & \text{FSH (Follicle Stimulating Hormone): Stimulates Sertoli cells in the seminiferous tubules, which provide nourishment and support for developing spermatogenic cells.} \\ \bullet & \text{LH (Luteinizing Hormone): Acts on Leydig cells (interstitial cells) to secrete testosterone. Testosterone promotes spermatogenesis and the maturation of spermatids into spermatozoa.} \\ \end{array}\]

Conclusion: Spermatogenesis ensures continuous production of sperm throughout the reproductive phase of a male, regulated by hormones FSH, LH, and testosterone.