Question

Why is it not possible to demonstrate respiration in a green plant kept in sunlight ?

Answer 1

During day time plants undergo photosynthesis. It is a process that requires light. In this process $O_2$ is given out by the plants and they take $C{O}_2$ to make their food. Hence, it cannot occur during night time. $O_2$ is consumed during respiration. It occurs both during the day as well as night. However, the rate of respiration is difficult to calculate during the day due to photosynthesis. Hence, it is not possible to demonstrate respiration in a green plant kept in sunlight.