Question

The transpiration in plants will be lowest

• A. When there is high humidity in the atmosphere.
• B. There is excess of water in the cell.
• C. Environmental conditions are very dry.
• D. High wind velocity.

Answer 1

The correct option is A When there is high humidity in the atmosphere.

Humidity is expressed as the percentage of water vapour present in the atmosphere. The relative humidity of the atmosphere affected the rate of transpiration to a great extent because it influences the DPD gradient between the intercellular spaces and outside atmosphere.

The higher the relative humidity of the outside atmosphere the lower will be the rate of transpiration. Conversely, the lower the relative humidity of the outside atmosphere the higher will be the rate of transpiration.