DNA replicates during:

Options

A. `G_2` phase
B. M Phase
C. S Phase
D. `G_1` Phase

Answer

To determine when DNA replicates during the cell cycle, we can follow these steps:

1. **Understand the Cell Cycle Phases**: The cell cycle consists of several phases: G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis). Each phase has distinct functions.

2. **Identify the Function of Each Phase**:
- **G1 Phase**: This is the first phase where the cell grows and prepares for DNA replication. It ensures that the cell has enough nutrients and energy.
- **S Phase**: This is the phase where DNA replication occurs. The amount of DNA in the cell doubles from 2N to 4N.
- **G2 Phase**: In this phase, the cell continues to grow and prepares for mitosis. It checks for any DNA damage and ensures everything is ready for division.
- **M Phase**: This is the phase where mitosis occurs, and the cell divides into two daughter cells.

3. **Focus on the S Phase**: Since the question specifically asks when DNA replicates, we need to focus on the S phase. This is the only phase where the actual replication of DNA takes place.

4. **Conclusion**: Based on the understanding of the cell cycle, the correct answer to the question "DNA replicates during:" is the S phase.

**Final Answer**: C) S phase

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