Terminally differentiated cells remains at which stage?

Options

A. `G_(1)` - phase
B. `G_(2)` - phase
C. `G_(0)` - phase
D. M - phase

Answer

### Step-by-Step Solution:

1. **Understanding Terminally Differentiated Cells**: Terminally differentiated cells are specialized cells that have completed the process of differentiation. This means they have developed into a specific type of cell that performs a unique function in the organism.

2. **Cell Cycle Overview**: The cell cycle is a series of events that cells go through as they grow and divide. It consists of several phases: G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis).

3. **Phases of the Cell Cycle**:
- **G1 Phase**: The cell grows and prepares for DNA replication.
- **S Phase**: DNA replication occurs.
- **G2 Phase**: The cell continues to grow and prepares for mitosis.
- **M Phase**: Mitosis occurs, leading to cell division.

4. **G0 Phase**: This is a phase where cells exit the cell cycle. Cells in this phase are not actively dividing or preparing to divide. They may perform their specialized functions without undergoing division.

5. **Terminally Differentiated Cells and G0 Phase**: When a cell becomes terminally differentiated, it typically enters the G0 phase. In this phase, the cell is metabolically active but does not divide. It carries out its specific functions in the body.

6. **Conclusion**: Therefore, terminally differentiated cells remain in the G0 phase of the cell cycle.

### Final Answer:
Terminally differentiated cells remain in the **G0 phase** of the cell cycle.

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