Haploid cells found within the seminiferous tubules of the testis are

Options

A. spermatogonia and spermatids
B. Secondary spermatocytes and spermatids
C. Secondary spermatocytes and primary spermatocytes
D. Spermatids and primary spermatocytes

Answer

To solve the question regarding the haploid cells found within the seminiferous tubules of the testis, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of the Testis**:
- The seminiferous tubules are the sites of sperm production in the testes.

2. **Identifying Germ Cells**:
- The germ cells involved in spermatogenesis include spermatogonia, primary spermatocytes, secondary spermatocytes, and spermatids.

3. **Determining the Ploidy of Each Cell Type**:
- **Spermatogonia**: These are diploid (2n) cells that contain 46 chromosomes.
- **Primary Spermatocytes**: These are also diploid (2n) cells that undergo meiosis.
- **Secondary Spermatocytes**: After the first meiotic division, these cells are haploid (n) and contain 23 chromosomes.
- **Spermatids**: These are the result of the second meiotic division and are also haploid (n) with 23 chromosomes.

4. **Identifying the Haploid Cells**:
- From the above analysis, we see that the haploid cells present in the seminiferous tubules are the secondary spermatocytes and spermatids.

5. **Evaluating the Options**:
- The options provided are:
- A) Spermatogonia and spermatids
- B) Secondary spermatocytes and spermatids
- C) Secondary spermatocytes and primary spermatocytes
- D) Spermatids and primary spermatocytes
- Based on our findings, the correct option is **B) Secondary spermatocytes and spermatids**.

### Final Answer:
The haploid cells found within the seminiferous tubules of the testis are **secondary spermatocytes and spermatids**.

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