Question

Given below is an experimental set-up to demonstrate a particular process. Study the same and answer the questions that follow: [5 MARKS]



(a) Name the physiological process being studied.
(b) Explain the process mentioned above.
(c) What is the aim of the above experiment?
(d) What would you observe in the experimental set-up after an hour? Give reason to support your answer.
(e) Mention any three adaptations found in plants to overcome the physiological process mentioned in (a) above.

Answer 1

Each Part: 1 Mark

(a) Rate of transpiration.
(b) The loss of water in the form of water vapours from the aerial parts such as the leaves and the green shoots of the plants is called transpiration.
(c) The aim of the experiment is to prove that more transpiration occurs from the lower surface of a leaf.
(d) After an hour, one would observe that the piece of cobalt chloride paper (blue) which is facing the upper surface of the leaf either does not turn pink or turns pink in a much longer time than the one on the lower surface which turns pink much faster. This proves that more transpiration takes place from the lower surface, which is on account of the numerous stomata found on it.
(e) Adaptations found in plants to overcome transpiration:
(i) Thick cuticle
(ii) Loss of leaves
(iii) Sunken stomata