AP BIOLOGY

Detailed explanation-1: -Therefore, when water exits, the guard cells relax, the stomata close, and diffusion rates are reduced. The closing of the stomata help the plant by preventing dehydration due to loss of water vapor, and helps with maintaining the water necessary for photosynthesis and the homeostasis, or internal balance of the plant.

Detailed explanation-2: -Guard cells are a pair of two cells that surround each stoma opening. To open, the cells are triggered by one of many possible environmental or chemical signals.

Detailed explanation-3: -Guard cells are located in the leaf epidermis and pairs of guard cells surround and form stomatal pores, which regulate CO2 influx from the atmosphere into the leaves for photosynthetic carbon fixation. Stomatal guard cells also regulate water loss of plants via transpiration to the atmosphere.

Detailed explanation-4: -The opening and closing of stomata is regulated by the integration of environmental signals and endogenous hormonal stimuli. The various different factors to which the guard cells respond translates into the complexity of the network of signaling pathways that control stomatal movements.