The immature male germ cells undergo division to produce sperms by the process of spermatogenesis. Choose the correct one with reference to above.

Options

A. Spermatogonia have 46 chromosomes and always undergo meiotic cell division
B. Primary spermatocytes divide by mitot- ic cell division
C. Secondary spermatocytes have 23 chro- mosomes and undergo second meiot- ic division
D. Spermatozoa are transformed into sper- matids

Answer

To solve the question regarding spermatogenesis and the immature male germ cells, we will follow these steps:

### Step-by-Step Solution:

1. **Understand Spermatogenesis**:
- Spermatogenesis is the process of sperm formation from immature male germ cells, specifically from spermatogonia.

2. **Identify the Germ Cells**:
- The immature male germ cells are called **spermatogonia**. These cells are diploid (2n), meaning they contain 46 chromosomes in humans.

3. **Mitosis of Spermatogonia**:
- Spermatogonia undergo **mitosis** to produce more spermatogonia. This is the initial step in spermatogenesis where the number of germ cells increases.

4. **Formation of Primary Spermatocyte**:
- One of the spermatogonia will differentiate and grow larger to become a **primary spermatocyte**. This cell is also diploid (2n) and contains 46 chromosomes.

5. **Meiosis I**:
- The primary spermatocyte undergoes **meiosis I**, resulting in two **secondary spermatocytes**. Each secondary spermatocyte is haploid (n), containing 23 chromosomes.

6. **Meiosis II**:
- Each secondary spermatocyte then undergoes **meiosis II**, producing a total of four **spermatids**. Each spermatid is also haploid (n), with 23 chromosomes.

7. **Differentiation into Spermatozoa**:
- Finally, the spermatids undergo differentiation to become **spermatozoa** (mature sperm). This process includes the development of a tail and other structural changes.

8. **Evaluate the Statements**:
- Now, we need to evaluate the statements provided in the question:
- **Statement A**: "Spermatogonia have 46 chromosomes." - This is correct.
- **Statement B**: "Spermatogonia always undergo meiotic division." - This is incorrect; they undergo mitotic division.
- **Statement C**: "Primary spermatocyte divides by mitotic cell division." - This is incorrect; it undergoes meiotic division.
- **Statement D**: "Secondary spermatocyte is 23 chromosomes and undergoes second meiotic." - This is correct; secondary spermatocytes are haploid and undergo meiosis II.
- **Statement E**: "Spermatids are transferred into spermatozoa." - This is incorrect; spermatids differentiate into spermatozoa.

9. **Conclusion**:
- The correct statement regarding spermatogenesis is that the **secondary spermatocyte has 23 chromosomes and undergoes second meiotic division**.

### Final Answer:
The correct statement with reference to spermatogenesis is that **the secondary spermatocyte is haploid (23 chromosomes) and undergoes meiosis II**.