Explain the role of flexibility of plasma membrane in the activity of the cell.

Explanation

### Step-by-Step Solution:

1. **Introduction to Plasma Membrane**:
- The plasma membrane is a vital component that surrounds all cells. It acts as a barrier that separates the internal environment of the cell from the external surroundings.

2. **Selective Permeability**:
- The plasma membrane is selectively permeable, meaning it allows certain substances to pass through while blocking others. This selective permeability is crucial for maintaining the cell's internal environment.

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