Answer in one or two word:
The kidney-shaped cells present in stoma.

Explanation

**Step-by-Step Solution:**

1. **Identify the Structure:** The question asks for the kidney-shaped cells present in the stoma of plants.

2. **Recall the Function:** These cells play a crucial role in the process of transpiration and gas exchange in plants.

3. **Name the Cell Type:** The specific type of cell that is kidney-shaped and surrounds the stomatal pore is known as a guard cell.

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