Which is the longest phase in the cell cycle of human liver cells?

Options

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

Answer

To determine the longest phase in the cell cycle of human liver cells, we can break down the cell cycle into its main phases and analyze their durations.

### Step-by-Step Solution:

1. **Understand the Cell Cycle Phases**: The cell cycle consists of several phases:
- G1 phase (Gap 1)
- S phase (Synthesis)
- G2 phase (Gap 2)
- M phase (Mitosis)

2. **Identify the Phases of Interphase**: The G1, S, and G2 phases together constitute what is known as Interphase. This is the phase where the cell grows, duplicates its DNA, and prepares for mitosis.

3. **Duration of Each Phase**:
- G1 phase: Approximately 11 hours
- S phase: Approximately 2 hours
- G2 phase: Approximately 2 hours
- M phase: Approximately 1 hour

4. **Calculate Total Time for Interphase**:
- Total time for Interphase (G1 + S + G2) = 11 hours (G1) + 2 hours (S) + 2 hours (G2) = 15 hours.

5. **Compare with M Phase**: The M phase, which is mitosis, takes significantly less time (approximately 1 hour).

6. **Conclusion**: Since Interphase (G1 + S + G2) takes up the majority of the cell cycle duration, it is the longest phase. In human liver cells, Interphase accounts for about 95% of the total time taken by a cell to divide.

### Final Answer:
The longest phase in the cell cycle of human liver cells is **Interphase**.

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