Question

Leaves that appear wilted during the daytime recovers at night because

• A. light is essential for photosynthesis
• B. stomata closes during night, temperature decreases, transpiration is reduced and plant is able to absorb more water from the soil
• C. transportation of organic substances increase during night
• D. All of the above

Answer 1

The correct option is B stomata closes during night, temperature decreases, transpiration is reduced and plant is able to absorb more water from the soil

During day time as the temperature increases, the rate of transpiration is high. If the plant is unable to absorb sufficient amounts of water then the leaves will wilt to reduce the surface area exposed to the sun. At night as the temperature decreases, the stomata gets closed and the rate of transpiration is low as compared to the amount of water absorbed. This helps the leaves in recovering and getting its shape back.
Light is essential for photosynthesis but it is not responsible for wilting of leaves.
Transportation of organic substances is not involved in the wilting and recovering phenomena.