. green plant kept in sunlight

Best Answer

It is not possible to demonstrate respiration in green plants kept in sunlight because during day time plants are undergoing photosynthesis. Photosynthesis requires CO₂ as the substrate in green plants. It takes place in the presence of light. CO₂ is also the product of respiration. During this time oxygen is given out by plants as a waste product and they take carbon dioxide to make food their own food. We know that the oxygen is consumed during respiration in plants hence it cannot be demonstrated at the daytime, as plants carry out respiration at night.