Question

Explain the process of opening and closing of stomata (without diagram).

Answer 1

Hint:The tiny openings or pores present in the plant tissue is known as stomata.

Complete answer:
Before understanding the process of opening and closing of stomata let us understand more about the stomata itself.
Stomata are tiny pore-like structures which are found in the leaves. They have many minute pores which are known as “stoma”. The stoma is surrounded by a pair of guard cells which are responsible for opening and closing of stomata. The cell wall around the soma is both flexible and tough. Guard cells are generally green colour due to the presence of stomata and are bean shaped.

Around the guard cells, subsidiary cells are present which are the accessory glands to the guard cells. The subsidiary cells are present in the epidermis between the guard cells and the epidermal cells.

There are different mechanisms responsible for opening and closing of the stomata. It is turgor pressure in guard cells which determines the opening and closing of stomata. When the guard cells are swelled because of water absorption, it leads to opening of the stomatal pores. Once the water is lost, the guard cells become flaccid and the stomata closes. Also, during the daytime stomata generally remain open and during the night they remain closed.

Note:There are various functions of stomata,
>They have a role in gaseous exchange
>They have a role in transpiration
>They prevent water loss at night