Photosynthesis occurs in the guard cells but not the epidermal cells. Explain why this is important in the control of the rate of transpiration in the plant

Need to figure out what the question is actually askingEssentially the question is explain how guard cells work and what their role isGuard cells will have more sugar than epidermal cells as epidermal cells do not photosynthesise. This causes osmosis of water from the epidermal cells to the guard cells (where water moves down a concentration gradient from an area of high concentration of water to an area of low concentration gradient down a water potential gradient)As the guard cell water content increases, they allow the stomata on the surface of the leaf to open and more water enters.