The chromosomes cluster at opposite poles and their identity is lost as discrete elements during

Options

A. Telophase
B. Anaphase
C. Metaphase
D. Prophase

Answer

To answer the question about when the chromosomes cluster at opposite poles and their identity is lost as discrete elements, we can analyze the stages of cell division.

### Step-by-Step Solution:

1. **Understanding Chromosome Structure**:
- Chromosomes consist of two sister chromatids joined at a region called the centromere. Each chromatid is a copy of the chromosome.

2. **Identifying the Stages of Mitosis**:
- Mitosis consists of several stages: prophase, metaphase, anaphase, and telophase. Each stage has distinct characteristics regarding the behavior of chromosomes.

3. **Prophase**:
- During prophase, chromosomes condense and become visible. The nuclear envelope begins to break down, and the spindle apparatus starts to form. However, the chromosomes are not yet at the poles.

4. **Metaphase**:
- In metaphase, chromosomes align at the metaphase plate (the equatorial plane of the cell). They are maximally condensed, but they are still identifiable as discrete elements.

5. **Anaphase**:
- During anaphase, the sister chromatids are pulled apart towards opposite poles of the cell. This is the stage where the separation begins, but the chromatids are still identifiable.

6. **Telophase**:
- In telophase, the separated chromatids reach the opposite poles of the cell. At this stage, they begin to de-condense and lose their distinct identities as separate chromatids. The nuclear envelope re-forms around each set of chromosomes, and they start to appear as a mass rather than discrete elements.

7. **Conclusion**:
- The correct answer to the question is **telophase**, as this is the stage where chromosomes cluster at opposite poles and their identity as discrete elements is lost.

### Final Answer:
The chromosomes cluster at opposite poles and their identity is lost as discrete elements during **telophase**.