Question

Amount of transpire water in beech tree in summer is
A. 2 times the fresh weight of its leaves.
B. 3 times of the fresh weight of its leaves
C. 4 times of the fresh weight of its leaves
D. 5 times the fresh weight of its leaves.

Answer 1

The process in which surplus of moisture from aerial parts of a plant is forfeited in the form of vapours is known as Transpiration. It is of three types namely: Lenticular transpiration, stomatal transpiration and cuticular transpiration. Stomata are present on the surface of the leaf of plants and open during the day time only.

Complete answer:
Several factors affect transpiration:

Light intensity: When the sunlight is sharp, the loss of water occurs more through the stomatal pores because the stomata are wide open. But the rate of transpiration is reduced during the night time because the stomata are closed.
Wind: The rate of transpiration increases as the velocity of wind increases. When wind blows, water vapour is carried away before the air around the leaf is drenched.
Atmosphere humidity: The rate of transpiration is reduced, if the air outside the plant is humid as the loss of internal water is affected.
Available Water: In case, the availability of water in the soil is low, then the rate of transpiration is also low and the leaves remain dehydrated.
For an acre of beech plants, they lost about 3000 gallons of water by transpiration each day. In one day, they lose water about 5 times the fresh weight of its leaves.

So the correct answer is Option D.

Note: Stomatal transpiration occurs by the loss of water through stomata. Stomata are present on the epidermis of green leaf and shoot and the opening and closing of stomata are controlled by guard cells. It is responsible for about 80-90 percent of total moisture loss while Lenticular transpiration occurs by the loss of water from lenticels present in fruits and woody stems and is responsible for about 1-5 percent of water loss only.