Question

Which of the following events occurs during spermiogenesis but not during spermatogenesis?

• A. Meiotic division of spermatocytes
• B. Formation of haploid cells
• C. Transformation of spermatids into spermatozoa
• D. Mitotic multiplication of spermatogonia

Hint:

Spermatogenesis produces spermatids, whereas spermiogenesis converts those spermatids into fully mature spermatozoa.

Answer 1

The Correct Option is C

Sperm formation in human males occurs inside the seminiferous tubules of testes through a complex process called spermatogenesis. This process begins at puberty and continues throughout reproductive life. Spermatogenesis includes several successive stages:
• Multiplication phase
• Growth phase
• Maturation phase
• Spermiogenesis During the multiplication phase, diploid spermatogonia divide repeatedly by mitosis to maintain the germ cell population. During the growth phase, spermatogonia enlarge to form primary spermatocytes. During the maturation phase, primary spermatocytes undergo meiosis-I to form secondary spermatocytes, which further undergo meiosis-II to produce haploid spermatids. At this stage, haploid cells have already been formed. However, spermatids are non-motile, rounded cells and cannot function as mature sperms. The final transformation of spermatids into mature spermatozoa is called spermiogenesis. During spermiogenesis:
• The nucleus becomes highly condensed
• Acrosome is formed from Golgi apparatus
• A flagellum develops for motility
• Mitochondria arrange in the middle piece
• Excess cytoplasm is discarded Thus, spermiogenesis specifically refers to morphological differentiation of spermatids into spermatozoa and is distinct from the earlier stages of spermatogenesis. Option analysis:
• Option (A): Incorrect because meiotic division occurs during maturation phase of spermatogenesis.
• Option (B): Incorrect because haploid spermatids are formed during meiosis.
• Option (C): Correct because spermiogenesis specifically converts spermatids into spermatozoa.
• Option (D): Incorrect because mitotic multiplication occurs in spermatogonia during early spermatogenesis. Therefore, the correct answer is: \[ \boxed{\text{(C)}} \]