Give reasons (AS1)

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

During the day time (in the presence of sunlight), the plants performs two processes viz. photosynthesis and respiration. In photosynthesis, plants make sugars and oxygen from carbon dioxide and water while in respiration, the plants use sugars and oxygen to make carbon dioxide and water. The rate of photosynthesis is higher than the rate of respiration during the daytime. Hence, it is difficult to measure the rate of respiration in plants in daylight.