Activity 6.8 NCERT class 10 science chapter 6 Life processes
Activity 6.8 asks us to cover a plant with a plastic sheet and see the result with respect to a pot covered with plastic without the plant.
Observation: Water droplet appeared in Plastic sheet having plant while no water droplet appears in a plastic sheet covered by the stick.
Explanation: Plant release water molecules in the air. A plastic sheet does not allow these molecules to escape. As a result, water droplets appear on the plastic sheet. A pot without plant does not get water molecules as there is no transpiration process going on. If in case few droplets appear then it is due to evaporation. Evaporation is a physical phenomenon, not a life process. In this case, the number of water droplets will be meagre.
A typical example of this phenomenon is the formation of dewdrops. Due to the low temperature in the morning water molecules released from plants condenses and form dew drops.
This suffices the transpirational pull theory; which says plant transpiration creates a pulling pressure in the roots, which result in water and mineral absorption.
Next: Life Process MCQ.
See also: Life process summary notes.