Biology
The given figure represents an experiment:
(a) Leaf A was coated with grease on both the surfaces.
(b) Leaf B was coated with grease on the lower surface.
(c) Leaf C was coated with grease on the upper surface.
(d) Leaf D was left without any application of grease.
All the four leaves A, B, C and D were left in a room for about 24 hours.
(i) Which leaf dries first? Give reason.
(ii) Which leaf dries last? Give reason.
Transpiration
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Answer
(i) Leaf D — The leaf with no greasing on either surfaces would dry first because it would lose water from both surfaces i.e. it would lose maximum quantity of water.
(ii) Leaf A — It was coated with grease on both the surfaces. Hence, it would dry last because greasing prevents evaporation of water and transpiration occurs through stomata which are present more on the lower surface of the leaf.
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