In spermatogenesis, reduction division of chromosome occurs during conversion of

Options

A. spermatogonia to primary spermatocytes
B. primary spermatocytes to secondary spermatocytes
C. secondary spermatocytes to spermatids
D. spermatids to sperms.

Answer

**Step-by-Step Solution:**

1. **Understanding Spermatogenesis**: Spermatogenesis is the process of sperm formation that occurs in the seminiferous tubules of the testes. It involves several stages of cell division and differentiation.

2. **Identifying the Starting Cell**: The process begins with a germ cell called spermatogonium, which is diploid (2n). At this stage, meiosis has not yet occurred.

3. **Mitosis of Spermatogonia**: The spermatogonia undergo mitotic division, increasing their numbers. Some of these cells differentiate into primary spermatocytes, which are still diploid.

4. **Meiosis Begins**: The primary spermatocytes then undergo the first meiotic division. This is where the reduction division occurs, as the diploid primary spermatocytes divide to form haploid secondary spermatocytes.

5. **Formation of Secondary Spermatocytes**: After the first meiotic division, each primary spermatocyte produces two secondary spermatocytes, which are haploid (n).

6. **Second Meiotic Division**: The secondary spermatocytes undergo a second meiotic division to produce four haploid spermatids, but the question specifically asks about the reduction division.

7. **Conclusion**: The reduction division of chromosomes occurs during the conversion of primary spermatocytes into secondary spermatocytes, which is the first meiotic division.

**Final Answer**: The reduction division of chromosomes occurs during the conversion of primary spermatocytes into secondary spermatocytes.

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