Question

How does light affect cellular respiration in plants?

Answer 1

Cellular respiration is the process by which glucose and oxygen are converted to carbon dioxide, energy and water. It doesn’t require sunlight and occurs in the mitochondria cell of living organisms. Photosynthesis requires sunlight.

Complete answer:
Process of cellular respiration in plants is as follows:
Photosynthesis in green plants produces glucose which in cellular respiration is converted into energy. The first stage is splitting of glucose into smaller molecules of pyruvate and a small amount of energy is released by the process of glycolysis which is an anaerobic process. Pyruvate molecules are reorganized and lead to the formation of carbon dioxide. Electrons then enter the electron transport chain to produce ATP. This step is an aerobic process as it requires oxygen.
Hence in other words in cellular respiration plants take in glucose and oxygen and release energy, carbon dioxide and water. Respiration occurs at every time of day and night. Gaseous exchange in plants occurs through stomata and lenticels.
In roots air is absorbed from spaces present between the particles of soil and oxygen is absorbed through the roots which help in the release of oxygen. In stems, oxygen enters and carbon dioxide exits through the stomata and lenticels. In leaves also stomata help in the exchange of gases via diffusion.

Note:
Metabolic pathway in which one glucose molecule is broken down into water and carbon dioxide and energy is released. Main steps of cellular respiration are glycolysis, pyruvate oxidation, citric acid cycle and oxidative phosphorylation. Light doesn’t play any role in any step of cellular respiration.