Which one of the following is correctly matched ?

Options

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

Answer

To determine which of the following options is correctly matched, we will analyze each option in detail:

### Step-by-Step Solution:

1. **Option A: Lipotene - Formation of Bifurcates**
- Lipotene is a stage in prophase I of meiosis where chromosomes begin to condense and become visible. However, the formation of bivalents (not bifurcates) occurs later in the zygotene stage. Therefore, this option is incorrectly matched.

2. **Option B: Diplotene - Chiasmata Appear**
- Diplotene is indeed a stage in prophase I of meiosis where the homologous chromosomes are paired and the chiasmata (the points where crossing over occurs) become visible. This option is correctly matched.

3. **Option C: Pachytene - Chiasmata Terminated**
- Pachytene is a stage where crossing over occurs, and chiasmata are formed. Chiasmata are resolved during the later stage called diakinesis, not pachytene. Therefore, this option is incorrectly matched.

4. **Option D: Zygote - Formation of Vaucut**
- The term "Vaucut" seems to be a typographical error or a misinterpretation. The correct term might refer to the formation of the "vacuole" or "vacuolar structures," which occurs during the lipotene stage. Thus, this option is also incorrectly matched.

### Conclusion:
The only correctly matched option is **Option B: Diplotene - Chiasmata Appear**.

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