Which one of the following is correctly matched?

Options

A. Leptotene -formation of bivalents
B. Diplotene -chiasmata formation
C. Pachytene -chiasmata terminalisation
D. Zygotene -formation of bouquet

Answer

To determine which of the given options is correctly matched, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Analyze Option A: Lipotene and Formation of Bifurcates**
- Lipotene is a stage in prophase I of meiosis.
- During Lipotene, the chromosomes start to condense and become visible, but bivalents (paired homologous chromosomes) are not yet formed.
- **Conclusion**: This option is incorrectly matched.

2. **Analyze Option B: Diplotene and Chiasmata Appear**
- Diplotene is also a stage in prophase I of meiosis.
- It is during this stage that the homologous chromosomes begin to separate slightly, and chiasmata (the points where crossing over occurs) become visible.
- **Conclusion**: This option is correctly matched.

3. **Analyze Option C: Pachytene and Chiasmata is Terminated**
- Pachytene is another stage in prophase I where crossing over occurs, and the chiasmata are formed.
- Chiasmata are not terminated until the next stage, which is diakinesis.
- **Conclusion**: This option is incorrectly matched.

4. **Analyze Option D: Zygote and Formation of Vaucut**
- Zygote refers to the fertilized egg, while "Vaucut" (likely a misspelling of "vacuole") does not relate to the zygote stage.
- The formation of vacuoles occurs in different contexts and is not specifically tied to the zygote.
- **Conclusion**: This option is incorrectly matched.

### Final Answer:
The correctly matched pair is **Option B: Diplotene and Chiasmata Appear**.

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