In a dicot pot herb, vaseline/vegetable oil was applied on the upper surface of one leaf (Experimental leaf 1) and on the lower surface of another leaf (Experimental leaf 2). Vaseline/Vegetable oil was not applied on the control leaf. The plant was deliberately not watered for several days. Which leaf will dry up last?
Experimental leaf 1
Experimental leaf 2
Control leaf
All the leaves will dry up simultaneously
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC NDA-1 – 2021
– Stomata are pores on the leaf surface, primarily on the lower surface in dicots, that regulate gas exchange and transpiration.
– Blocking stomata reduces the rate of transpiration and thus water loss.
– The control leaf loses water normally from both surfaces (mainly lower).
– Since Experimental leaf 2 loses the least amount of water due to blocked stomata on the lower surface, it will dry up last among the three leaves when the plant is not watered.