Which is the following statements is not correct about spermatogenesis ?

Options

A. Spermatogonia multiply by mitotic division and increase in number
B. Each spermatogonium is diploid and contains 46 chromosomes
C. Some spermatogonia periodically undergo mitosis
D. A primary spermatocyte completes fist meiotic division leading to formation of two equal haploid cells called secondary spermatocyte

Answer

To determine which statement about spermatogenesis is incorrect, we will analyze each statement provided in the options.

### Step-by-step Solution:

1. **Understanding Spermatogenesis**:
- Spermatogenesis is the process of sperm production in males, occurring in the seminiferous tubules of the testes.

2. **Analyzing the First Statement**:
- **Statement**: "Spermatogonia multiply by mitotic division and increase in number."
- **Analysis**: This statement is correct. Spermatogonia, which are the stem cells for sperm, undergo mitosis to increase their number.

3. **Analyzing the Second Statement**:
- **Statement**: "Each spermatogonium is diploid and contains 46 chromosomes."
- **Analysis**: This statement is also correct. Spermatogonia are diploid cells, meaning they have two sets of chromosomes (46 in total).

4. **Analyzing the Third Statement**:
- **Statement**: "Some spermatogonias periodically undergo meiosis."
- **Analysis**: This statement is incorrect. While spermatogonia undergo mitosis, it is the primary spermatocytes that undergo meiosis, not the spermatogonia themselves.

5. **Analyzing the Fourth Statement**:
- **Statement**: "Primary spermatocytes complete the first meiotic division leading to the formation of two haploid cells called secondary spermatocytes."
- **Analysis**: This statement is correct. Primary spermatocytes undergo meiosis I to produce two haploid secondary spermatocytes.

### Conclusion:
The statement that is not correct about spermatogenesis is the third statement: "Some spermatogonias periodically undergo meiosis."

### Final Answer:
The incorrect statement about spermatogenesis is: **"Some spermatogonias periodically undergo meiosis."**

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