What will happen when the leaf of a sensitive plant is touched ?

Explanation

**Step-by-Step Solution:**

1. **Identify the Plant**: The sensitive plant is scientifically known as *Mimosa pudica*. It is important to know the common and scientific names to understand the context of the question.

2. **Response to Touch**: When the leaf of the sensitive plant is touched, it exhibits a rapid response. The leaves fold up and the stem droops. This is a distinctive characteristic of the plant.

3. **Mechanism of Response**: The folding of the leaves and drooping of the stem occur due to a change in turgor pressure within the plant cells. Turgor pressure is the pressure of the fluid inside the cell against the cell wall, which helps maintain the plant's structure.

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