Question

opening and closing of stomata is due to

Answer 1

The opening and closing of stomata takes place due to the presence of guard cells in the leaf.

You can find such guard cells surrounding each stoma, and the cells can regulate the rate of transpiration by opening and closing the stomata.

If the guard cells lose water then it can cause the cells to become flaccid.

Answer 2

The opening and closing of the pore is a function of the guard cells. The guard cells swell when water flows into them, causing the stomatal pore to open. Simillarly the pore closes if the guard cells shrink