What are stomata and their function?

When a leaf is examined under the microscope, we observe many tiny pores, which are collectively called stomata.

Stomata are the minute openings, generally found in the epidermis of leaves. They are typically found in plant leaves and can also be found in stems and other parts of plants.  Stomata play an important role by permitting the movement of gases such as oxygen, carbon dioxide, and water vapour to diffuse between the interior and outer surface of the plant tissues.

The main functions of stomata are:

1. Helps in the exchange of gases by opening and closing the pores in the leaves.
2. It helps to expel the excess water out from the leaves in the form of water vapour.
3. Based on the weather conditions, it closes or opens its pores to maintain the moisture balance.
4. Allows the uptake of carbon dioxide and to give out oxygen during the process of photosynthesis.
5. Stomata remain open during the day and closed at night. This closure prevents water from escaping through open pores.