Which of the following is diploid ?

Options

A. Secondary spermatocytes
B. Spermatozoa & ova
C. Spermatogonia , Oogonia , Primary spermatocyte
D. Secondary oocytes

Answer

To determine which of the following is diploid, we need to analyze each option provided in the question. The options are: secondary spermatocytes, spermatozoa, ova, spermatogonia, oogonia, primary spermatocyte, and secondary oocytes.

### Step-by-Step Solution:

1. **Understanding Diploid and Haploid**:
- Diploid cells contain two sets of chromosomes (2n), while haploid cells contain one set of chromosomes (n). In humans, diploid cells have 46 chromosomes, while haploid cells have 23 chromosomes.

2. **Analyzing Each Option**:
- **Secondary Spermatocytes**: These are haploid (n) as they are formed after the first meiotic division of primary spermatocytes.
- **Spermatozoa**: These are also haploid (n) gametes formed after the second meiotic division.
- **Ova**: These are haploid (n) as they are the female gametes produced after meiosis.
- **Spermatogonia**: These are diploid (2n) cells that undergo mitosis to produce primary spermatocytes.
- **Oogonia**: These are diploid (2n) cells that undergo mitosis to produce primary oocytes.
- **Primary Spermatocyte**: These are diploid (2n) cells that undergo meiosis to form secondary spermatocytes.
- **Secondary Oocytes**: These are haploid (n) cells formed after the first meiotic division of primary oocytes.

3. **Identifying Diploid Cells**:
- From the analysis, we find that **spermatogonia**, **oogonia**, and **primary spermatocyte** are diploid cells.

4. **Conclusion**:
- The options that are diploid are **spermatogonia**, **oogonia**, and **primary spermatocyte**. If we need to select one option, we can choose **spermatogonia** as a representative diploid cell.

### Final Answer:
The diploid cells among the options are **spermatogonia** and **primary spermatocyte**.