At which phase of meiosis, the sister chromatids move towards opposite poles?

Options

A. anaphase I
B. anaphase II
C. metaphase I
D. metaphase II

Answer

To determine the phase of meiosis during which sister chromatids move towards opposite poles, we can break down the process of meiosis step by step.

### Step-by-Step Solution:

1. **Understanding Meiosis**: Meiosis is a two-part cell division process that reduces the chromosome number by half, resulting in four haploid cells. It consists of two main stages: Meiosis I and Meiosis II.

2. **Meiosis I Overview**:
- **Prophase I**: Homologous chromosomes pair up to form bivalents (tetrads), and crossing over occurs.
- **Metaphase I**: Tetrads align at the cell's equatorial plane.
- **Anaphase I**: The homologous chromosomes (not sister chromatids) are pulled apart to opposite poles. This is where the tetrads separate.

3. **Meiosis II Overview**:
- **Prophase II**: Chromosomes condense again, and the spindle apparatus forms.
- **Metaphase II**: Chromosomes line up at the equator of the cell.
- **Anaphase II**: This is the critical phase where sister chromatids are separated and move towards opposite poles.

4. **Identifying the Correct Phase**:
- In **Anaphase I**, homologous chromosomes separate, but sister chromatids remain together.
- In **Anaphase II**, the sister chromatids are separated and move towards opposite poles of the cell.

5. **Conclusion**: The phase of meiosis in which sister chromatids move towards opposite poles is **Anaphase II**.

### Final Answer:
The phase of meiosis during which sister chromatids move towards opposite poles is **Anaphase II**.