In mitosis, nuclear envelope and nucleolus disappear during

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks during which phase of mitosis the nuclear envelope and nucleolus disappear.

2. **Identifying the Phases of Mitosis**: Mitosis consists of several phases: prophase, metaphase, anaphase, and telophase. Interphase is not a part of mitosis.

3. **Analyzing Interphase**: Interphase is a resting phase where the cell prepares for division. During this phase, the nuclear envelope and nucleolus are present, so this option can be eliminated.

4. **Analyzing Telophase**: Telophase is the final phase of mitosis. During this phase, the nuclear envelope and nucleolus reappear, which means this option can also be eliminated.

5. **Analyzing Prophase**: In prophase, chromatin condenses into visible chromosomes. During this phase, the nuclear envelope starts to disintegrate, and the nucleolus disappears. Therefore, both the nuclear envelope and nucleolus are absent in this phase.

6. **Analyzing Metaphase**: Metaphase follows prophase. While the nucleolus may be absent, the nuclear envelope is already disintegrated. The disappearance of the nucleolus marks the beginning of metaphase, but it does not disappear during this phase.

7. **Conclusion**: Based on the analysis, the correct answer is that both the nuclear envelope and nucleolus disappear during **prophase**.

**Final Answer**: The nuclear envelope and nucleolus disappear during **prophase**.

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