question_answer

  Leaves of a healthy potted plant were coated with vaseline to block the stomata. Will this plant remain healthy for long? State three reasons for your answer.  

Answer:

                  If waxy coating is made on the surface of leaf, loss of water in the form of water vapour does not take place. Even the gaseous exchange will not take place. So, photosynthesis will either be reduced or will not take place. The plant will not remain healthy for long because: (a) Exchange of gases will not take place. (b) Photosynthesis will either be reduced or will not take place due to lack of CO2. (c) Transpiration will not take place, so there will be no mechanism of cooling in hot weather.