The homologous , chromosomes line up at the equator in pairs, name of phase and sequence

Options

A. metaphase of mitosis
B. metaphase of meiosis-1
C. both metaphase of meiosis
D. both (a) and (b)

Answer

To solve the question regarding the phase in which homologous chromosomes line up at the equator in pairs, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chromosome Behavior in Cell Division**:
- In cell division, chromosomes undergo specific arrangements during different phases. It's essential to distinguish between mitosis and meiosis.

2. **Identifying the Relevant Phases**:
- In mitosis, chromosomes line up at the equator during metaphase, but they are sister chromatids, not homologous chromosomes.
- In meiosis, there are two stages: Meiosis I and Meiosis II. During Meiosis I, homologous chromosomes pair up.

3. **Focusing on Meiosis I**:
- During **Metaphase I of Meiosis**, homologous chromosomes (each consisting of two sister chromatids) align at the equatorial plane of the cell. This is a crucial step for the reduction division that occurs in meiosis.

4. **Conclusion**:
- The phase where homologous chromosomes line up at the equator in pairs is **Metaphase I of Meiosis**.

### Final Answer:
The homologous chromosomes line up at the equator in pairs during the **Metaphase of Meiosis I**.

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