DENDROLOGY

Detailed explanation-1: -These cells are called guard cells and subsidiary cells. Guard cells are large crescent-shaped cells, two of which surround a stoma and are connected to at both ends. These cells enlarge and contract to open and close stomatal pores.

Detailed explanation-2: -Stomatal guard cells also regulate water loss of plants via transpiration to the atmosphere. Signal transduction mechanisms in guard cells integrate a multitude of different stimuli to modulate stomatal aperture. Stomata open in response to light.

Detailed explanation-3: -Upon the incoming of water inside the guard cells, they swell up to become like a curved banana surface, due to which the stomatal pore opens up. When the guard cells lose water, they become flaccid and straight and thus, close the stomatal aperture. Guard cells and stomata regulates the respiration process in plants.