Chiasmata can be distinctively seen in

Options

A. Zygotene
B. Pachytene
C. Diplotene
D. Diakinesis

Answer

**Step-by-Step Solution:**

1. **Understanding Chiasmata**: Chiasmata are X-shaped structures that form during meiosis, specifically during the process of crossing over, where segments of non-sister chromatids exchange genetic material.

2. **Identifying the Stages of Prophase 1**: Prophase 1 of meiosis is divided into five substages:
- Leptotene
- Zygotene
- Pachytene
- Diplotene
- Diakinesis

3. **Analyzing Each Stage**:
- **Zygotene**: Homologous chromosomes begin to pair up, but chiasmata are not yet visible.
- **Pachytene**: Crossing over occurs, and chiasmata start to form, but they are not distinctly visible yet.
- **Diplotene**: The synaptonemal complex begins to dissolve, and chiasmata become more prominent and distinct.
- **Diakinesis**: The chromosomes condense further, and chiasmata are still visible, but they are not newly formed.

4. **Conclusion**: Chiasmata can be distinctly seen in the **Diplotene** stage of Prophase 1, as this is when they become prominent due to the dissolution of the synaptonemal complex.

5. **Final Answer**: The correct answer is **Diplotene**.

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