Question

State four factors that affect transpiration.

Answer 1

Transpiration:

1. Loss of water vapour from the surface of the plant, mainly by stomata on the leaves is transpiration.
2. Transpiration helps in the cooling effect, transport of minerals and uptake of water.

Factors that affect transpiration:

1. Sunlight:
   1. When there is sunlight, the stomata remain open for the diffusion of gases, hence transpiration is more during the day.
   2. When there is no sunlight, the stomata get closed so the transpiration becomes less.
2. Temperature:
   1. Transpiration increases with the rise in temperature.
   2. Transpiration is more during summers than in winters.
   3. Also, it is more in the afternoon when the temperature is higher than in the evening.
3. Humidity:
   1. High humidity means more water vapour in the air.
   2. Transpiration is less when there is high humidity in the air (like on a rainy day).
4. Wind:
   1. Transpiration is more when the wind blows faster as the water vapours get removed faster from the leaves.