what is stomata?

 

Stomata is a microscopic pore on the surface (epidermis) of land plants.  In plants exchange of gases occurs mostly through stomata. Intake of Oxygen and release of carbon di oxide occurs through stomata. The immediate cause of the opening or closing of the stomata is a change in the turgidity of the guard cells. The inner wall of each guard cell, towards the pore is elastic and thick. Increased turgidity, opens the stomata and vice versa. Cell wall of guard cells has microfibrils that help this process.