In which phase of the ceII cycle are the chromosomes inactive, condensed, and not transcribed to messenger RNA?

Options

A. `G_(1)` phase.
B. S phase
C. M phase
D. `G_(2)` phase

Answer

To determine in which phase of the cell cycle the chromosomes are inactive, condensed, and not transcribed to messenger RNA, we can analyze the different phases of the cell cycle.

### Step-by-Step Solution:

1. **Understanding the Cell Cycle Phases**:
- The cell cycle consists of several phases: G1 phase (Gap 1), S phase (Synthesis), G2 phase (Gap 2), and M phase (Mitosis).
- Each phase has distinct activities related to cell growth, DNA replication, and division.

2. **Analyzing Each Phase**:
- **G1 Phase**: This is the first gap phase where the cell grows and synthesizes proteins and enzymes necessary for DNA replication. Chromosomes are not condensed and are actively involved in transcription.
- **S Phase**: During this phase, DNA replication occurs. The chromosomes are duplicated, but they are still not condensed and are actively being transcribed.
- **G2 Phase**: In this phase, the cell continues to grow and prepares for mitosis. There is protein synthesis, and the chromosomes are still not fully condensed.
- **M Phase**: This is the mitotic phase where the cell divides. During this phase, chromosomes condense and become visible under a microscope. They are inactive in terms of transcription, meaning they do not produce messenger RNA.

3. **Conclusion**:
- The correct answer is **M Phase**. In this phase, the chromosomes are condensed, inactive, and not transcribed to messenger RNA.

### Final Answer:
The phase of the cell cycle in which the chromosomes are inactive, condensed, and not transcribed to messenger RNA is the **M Phase**.

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