Question

Who said that “transpiration is a necessary evil”?
A. Bose
B. Steward
C. Anderson
D. Curtis

Answer 1

Hint: The loss of water in the form of vapors from the aerial parts of the plant is called transpiration. It occurs through stomata which are the microscopic regulated pore complexes that occur in epidermis of leaves and other soft plant organs.

Complete answer: The various advantages of transpiration are:
It controls the rate of absorption of water from soil.
It helps in absorption of mineral salts.
It regulates the plant temperature and contributes to cooling of leaves and surrounding air. It protects the leaves from heating injury, particularly under the conditions of high temperature and intense sunlight.
It is responsible for the ascent of sap.
It helps in maintaining plant’s shape and structure by keeping the cells turgid.
It also supplies water for photosynthesis.
The disadvantages of transpiration for the plants are:
About 98% of water absorbed by land plants is transpired so the magnitude of water transpired is considerably high.
It may cause water shortage and injury to the plants by desiccation.
So transpiration is a natural consequence of the basic facts of leaf anatomy. Mesophyll cells with a lot of intercellular spaces with stomata are essentially meant for gaseous exchange. Required for important processes like photosynthesis, and respiration. Leaf with this of anatomy, unavoidably is responsible for the process of transpiration. Therefore transpiration has therefore been rightly called a necessary evil by Curtis (1926).
So, the correct answer is “Option D”.

Note: Antitranspirants are the chemicals that are sprayed on the crop plants for reducing the rate of transpiration as high rate of transpiration causes wilting in the plant and also reduces the yield of the crop.