Question

Explain the structure and working of stomata with the help of a suitable diagram.

Answer 1

Structure of stomata:

1. Stomata are tiny pores or openings present on the surface of the leaf.
2. They are surrounded by bean shaped guard cells.
3. Guard cells regulate the opening and closing of stomata.
4. Subsidiary cells surround the guard cells.

Mechanism of stomatal opening and closing:

1. The opening and closing of stomata is dependent on turgor pressure.
2. When water enters the guard cells and they become turgid, they expand resulting in the opening of stomata.
3. When the guard cells lose water, they become flaccid leading to stomatal closure.
4. It is light directed.
5. The stomata opens during the day and closes at night.