HORTICULTURE

Detailed explanation-1: -Stomatal guard cells play a key role in the ability of plants to survive on dry land, because their movements regulate the exchange of gases and water vapor between the external environment and the interior of the plant.

Detailed explanation-2: -Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata. Light is the main trigger for the opening or closing.

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.

Detailed explanation-4: -They aid in the flow of gases between the atmosphere and plants. Guard cells regulate the opening and closing of stomatal holes, which are controlled by the process called osmosis. The entry of water into the stomata makes guard cells swell which leads to the opening of the stomata.