Question 16
Observe the figure of an activity given, carried out with leaves of plants and polythene bag. Now answer the following.
(a) Which process is demonstrated in the activity?
(b) When will this activity show better results on a bright sunny day or a cloudy day?
(c) What will you observe in the polythene bag after few hours of setting up the activity?
(d) Mention any one precaution you must take while performing this activity?
(a) The process demonstrated in the activity is transpiration. The process in which water comes out of leaves in the form of vapour is called transpiration.
(b) The environmental factors that affect transpiration are- temperature, light, humidity and wind speed. Transpiration becomes maximum when the temperature is more. Therefore, the activity will show better results on a bright sunny day.
(c) After a few hours of setting up the activity, one can observe small droplets of water inside the polythene bag. Since the leaves are enclosed in a polythene bag, the water that comes out of the leaves in form of vapour gets deposited on the polythene bag.
(d) A major precaution one must take while performing this activity is that the polythene bag should be clean and dry and its mouth should be sealed properly to make the set-up air-tight.