AP BIOLOGY

Detailed explanation-1: -They help to regulate the rate of transpiration by opening and closing the stomata. Light is the main trigger for the opening or closing. Each guard cell has a relatively thick cuticle on the pore-side and a thin one opposite it.

Detailed explanation-2: -Guard cells are pairs of epidermal cells that control gas diffusion by regulating the opening and closure of stomatal pores.

Detailed explanation-3: -Guard cells use osmotic pressure to open and close stomata, allowing plants to regulate the amount of water and solutes within them. In order for plants to produce energy and maintain cellular function, their cells undergo the highly intricate process of photosynthesis .

Detailed explanation-4: -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-5: -As the potassium ions accumulate in the guard cell, the osmotic pressure is lowered. A lower osmotic pressure attracts water to enter the cell. As water enters the guard cell, its hydrostatic pressure increases. The pressure causes the shape of the guard cells to change and a pore is formed, allowing gas exchange.