To produce 200 spematozoa

Options

A. only 100 primary spermatocytes are required
B. only 200 secondary spermatocytes are required
C. only 50 secondary spermatocytes are required
D. only 200 spermatids are required

Answer

To solve the problem of how many primary spermatocytes are needed to produce 200 spermatozoa, we can break down the process of spermatogenesis step by step.

### Step-by-Step Solution:

1. **Understand the Process of Spermatogenesis**:
- Spermatogenesis is the process of sperm formation that occurs in the male reproductive system. It begins with spermatogonia, which are the stem cells.

2. **Formation of Primary Spermatocytes**:
- Spermatogonia undergo mitotic division to produce primary spermatocytes. Each primary spermatocyte will eventually undergo meiosis.

3. **Meiosis of Primary Spermatocytes**:
- Each primary spermatocyte undergoes meiosis I to form two secondary spermatocytes. Therefore, from one primary spermatocyte, we get 2 secondary spermatocytes.

4. **Meiosis of Secondary Spermatocytes**:
- Each secondary spermatocyte then undergoes meiosis II to produce two spermatids. Thus, from two secondary spermatocytes, we get a total of 4 spermatids from one primary spermatocyte.

5. **Conversion of Spermatids to Spermatozoa**:
- Each spermatid matures into a spermatozoon (sperm). Therefore, from one primary spermatocyte, we can produce 4 spermatozoa.

6. **Calculate the Number of Primary Spermatocytes Needed**:
- To produce 200 spermatozoa, we need to determine how many primary spermatocytes are required.
- Since 1 primary spermatocyte produces 4 spermatozoa, we can calculate the number of primary spermatocytes needed:
\[ \text{Number of primary spermatocytes} = \frac{200 \text{ spermatozoa}}{4 \text{ spermatozoa per primary spermatocyte}} = 50 \]

### Conclusion:
To produce 200 spermatozoa, **50 primary spermatocytes** are required.

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