The diagram of an apparatus given below demonstrates a particular process in plants. Study the same and answer the questions that follow: The diagram of an apparatus given below demonstrates a particular process in plants. Study the same and answer the questions that follow:
Name the structures in a plant through which the above process takes place.
Topic: Structures through which transpiration occurs
Answer
STOMATA (of the leaves), LENTICELS (of woody stems) and the CUTICLE.
Name all THREE, since the question says "structures" in the plural.
The three kinds of transpiration, by how much each contributes: STOMATAL — through the STOMATA of the leaves; by far the greatest, about 90% CUTICULAR — through the waxy CUTICLE; small, and smaller still when the cuticle is thick LENTICULAR — through the LENTICELS of woody stems; least of all
Note that only the STOMATA can be OPENED AND CLOSED, by the guard cells. Lenticels are permanently open and the cuticle cannot be regulated at all — which is why a plant in drought can reduce but never stop its water loss.