Question

Describe briefly, the mechanism of stomatal opening and closing.

Answer 1

There are different mechanisms which are responsible for the opening and closing of the stomata. The opening and closing depends upon the turgor pressure in the guard cells. The swelling of guard cells due to absorption of water causes opening of stomatal pores while shrinking of guard cells closes the pores. Opening and closing of stomata occurs due to turgor changes in guard cells. When guard cells are turgid, stomatal pore is open while in flaccid conditions, the stomatal aperture closes. There are other theories which explains the opening and the closing of the stomatal pore.