AP BIOLOGY

Detailed explanation-1: -The cuticle reduces the rate of water loss from the leaf surface.

Detailed explanation-2: -To reduce water loss the leaf is coated in a waxy cuticle to stop the water vapour escaping through the epidermis.

Detailed explanation-3: -Leaves are covered by a waxy cuticle on the outer surface that prevents the loss of water. Plants that grow in dry environments and plants that grow on other plants (epiphytes) have a much thicker waxy cuticle than those growing in more moderate, well-watered environments (Figure 17.1.

Detailed explanation-4: -Sunken stomata ensure less water loss, thus reduces the rate of transpiration. Hence, these are characteristically found in xerophytes. In order to reduce transpiration, a maximum number of stomata in a dorsiventral leaf are present on the lower surface.

Detailed explanation-5: -Water loss through transpiration can be reduced by closing the stomata in the leaves using a substance called ABA. When the stomata is closed photosynthesis will decrease because no CO2 can enter through the closed stomata. Less photosynthesis means less energy is produced by the plant and the plant stops growing.