Final answer:
Stomatal opening and closing is regulated by the activation of the proton-pump in guard cells, which controls turgor pressure by managing solute and water movement, facilitating gas exchange for photosynthesis and transpiration.
Step-by-step explanation:
Regulators of stomata opening and closing work primarily by activating the proton-pump in guard cells. Guard cells regulate the movement of gases by altering the size of the stomatal pores on the leaf surface. These cells swell to open the stomata when they accumulate solutes, primarily potassium ions (K+), which are actively transported into the cells. Water then follows by osmosis, increasing turgor pressure within the guard cells and leading to the opening of the stomata. Conversely, when solutes are lost from the guard cells, they become flaccid, and the stomata close. This process is crucial for a plant's ability to take in carbon dioxide for photosynthesis and limit water loss through transpiration, both of which are vital for maintaining a continuous upward flow of water from the roots to the leaves.