Question

(a) Leaves of a healthy potted plant were coated with vaseline. Will this plant remain healthy for long? Give reason for your answer.
(b) What will happen to the rate of photosynthesis on a plant under the following circumstances?
(i) cloudy day in morning but bright sunshine in the afternoon
(ii) no rainfall in the area for a considerable time.
(iii) gathering of dust on the leaves

Answer 1

(a) If leaves of a healthy potted plant were coated with vaseline, it will not remain healthy for long. Due to the coating of vaseline, the stomatal pores will be blocked. Hence, the plant will not be able to get oxygen for respiration and carbon dioxide for photosynthesis. Transpiration will also stop and the plant will ultimately die.

(b) The rate of photosynthesis will:
(i) first decrease as there will be less sunlight and then increase during the afternoon
(ii) decrease due to less availability of water
(iii) decrease due to the closed stomatal pores