Which of the phases of cell cycle is of longest duration ?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Cell Cycle**: The cell cycle consists of several phases that a cell goes through during its life. These phases include interphase and the mitotic phase (M phase).

2. **Identifying Interphase**: Interphase is the period of the cell cycle when the cell is not dividing. It is crucial for the growth and preparation of the cell for division.

3. **Breaking Down Interphase**: Interphase is further divided into three sub-phases:
- **G1 Phase (Gap 1)**: This is the first phase after cell division where the cell grows and carries out its normal functions. DNA replication does not occur in this phase.
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