Which of the following is not haploid?

Options

A. Primary spermatocyte
B. Spermatogonia
C. Ootid
D. Both (a) and (b)

Answer

To solve the question "Which of the following is not haploid?" we need to analyze the options provided: primary spermatocyte, spermatogonia, ootid, and both A and B.

### Step-by-Step Solution:

1. **Understanding Haploid and Diploid**:
- Haploid cells contain one complete set of chromosomes (n), while diploid cells contain two complete sets (2n).

2. **Analyzing Spermatogonia**:
- Spermatogonia are the precursor cells to sperm. They are diploid, meaning they contain 46 chromosomes (2n). They are located at the periphery of the seminiferous tubules in the testes.

3. **Analyzing Ootid**:
- An ootid is the final stage of oocyte development after the second meiotic division. Ootids are haploid, containing only 23 chromosomes (n).

4. **Analyzing Primary Spermatocyte**:
- Primary spermatocytes are also diploid cells. They arise from spermatogonia and contain 46 chromosomes (2n). They undergo meiosis to produce secondary spermatocytes, which are haploid.

5. **Conclusion**:
- Since both spermatogonia and primary spermatocytes are diploid, the correct answer to the question "Which of the following is not haploid?" is **both A (spermatogonia) and B (primary spermatocyte)**.

### Final Answer:
**Both A and B (spermatogonia and primary spermatocyte) are not haploid.**

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