Question

Given below is the diagram of an experimental set up to study the process of transpiration in plants. Study the same and then answer the questions that follow:

(i) What is the colour of dry cobalt chloride paper?
(ii) Is the experimental leaf a monocot or a dicot? Give a reason to support your answer.
(iii) Why axe glass slides placed over the dry cobalt chloride papers?
(iv) After about half an hour what change, if any, would you expect to find in the cobalt chloride paper placed on the dorsal and ventral sides of the leaf? Give a reason to support your answer.
(v) Define the term ‘transpiration’.

Answer 1

(i) The colour of dry cobalt chloride paper is blue.
(ii) Dicot leaf. It has reticulate venation.
(iii) To prevent water vapour of the air from interfering the experiment. .
(iv) The cobalt chloride paper placed on the lower surface of the leaf will show more pink dots as there are more stomata. The upper surface has less stomata than the lower surface.
(v) Loss of water as water vapour from the aerial parts of the plant.