Question

What are stomata? Explain the functions and the opening and closing of stomata? [3 MARKS]

Answer 1

Definition: 1 Mark
Opening mechanism: 1 Mark
Function: 1 Mark

Stomata are minute apertures found typically on the outer leaf skin layer, also known as the epidermis. Stomatal opening is guarded by two bean-shaped cells called
guard cells. When guard cells are turgid i.e. filled with water, the stomatal pore opens and when guard cells lose water and become flaccid, the stomatal pore closes.
Their main function is to allow diffusion of gases such as carbon dioxide, water vapour, and oxygen.