Question

Photosynthesis requires sunlight and water. Leaves are broad and flat to maximize exposure to the sun, but how do they retain water since all that sunlight should cause a lot of evaporation?

a. Through a waxy, water-resistant outer layer called the cuticle.
b. By actively pumping water from the roots to the leaves, regulating the water balance.
c. Utilizing specialized cells like guard cells that control the opening and closing of pores (stomata) to reduce water loss.
d. By storing excess water in specialized cells within the leaf structure.

Answer 1

Leaves have a waxy outer layer called the cuticle to prevent water loss and stomata regulated by guard cells to balance water retention with gas exchange for photosynthesis.

Step-by-step explanation:

Leaves retain water and manage evaporation in several ways despite their broad and flat surfaces which are necessary to maximize exposure to sunlight for photosynthesis. One of the primary methods is through a waxy, water-resistant outer layer of the leaf called the cuticle. This coating is particularly critical in preventing water loss. Another crucial adaptation involves the stomata, which are small pores on the leaf surface flanked by specialized cells known as guard cells. These guard cells regulate the opening and closing of the stomata in response to various environmental factors, thereby controlling water loss while still allowing gas exchange necessary for photosynthesis. The strategic location of stomata, usually on the underside of leaves, further helps in reducing water loss.