Question

What causes the opening and closing of stomata?

Answer 1

Stomata:

1. Stomata are the tiny pores found on the surface of the leaves.
2. During transpiration, the stomata regulate the rate of gaseous exchange.
3. These small pores are found in epidermis cells and can be opened or closed.
4. Multiple mechanisms control the opening and closing of stomata to control the function of transpiration.
5. Stomata close during high temperatures and do not reopen to allow the leaf to cool.

Guard cells:

1. Stomata are made up of two guard cells.
2. Stomata, for example, is surrounded by guard cells.
3. They are primarily in charge of opening and closing the stomata to regulate the rate of transpiration.
4. These cells resemble bean or dumbbell shapes.
5. These cells are later modified to form subsidiary cells
6. The inner side of the guard cell walls is thick and elastic, while the outer cell wall is thin.
7. Inside the guard cells, there are several microfibrils that aid in the opening and closing of the guard cells.
8. Stomata open and close due to changes in the turgidity or water level of these cells.

Opening and Closing of guard cells:

1. During transpiration, the transport of potassium ions into and out of the guard cells causes stomata to open and close.
2. When exposed to light during the day, potassium ions enter the guard cells.
3. This causes the water potential in the guard cells to drop and water to enter the guard cells.
4. This causes the guard cells to swell and become turgid, resulting in the opening of stomata pores.
5. In the absence of light at night, potassium ions exit guard cells, and water potential increases in the guard cells.
6. As a result, the water of guard cells escapes and the cell shrinks, causing the stomata pores to close.