Describe the different types of respiration that takes place in plants.

Depending upon the presence or absence of oxygen, respiration is of two types — aerobic respiration and anaerobic respiration.

Aerobic respiration — When the oxidation of food (glucose) takes place in the presence of oxygen, it is called aerobic respiration. In this process, glucose is completely oxidized to form carbon dioxide and water. It takes place in mostly higher animals and plants. In aerobic respiration, 38 ATP molecules are released from oxidation of one glucose molecule.

Glucose + Oxygen ⟶ Carbon dioxide + Water + Energy (38 ATP)

Anaerobic respiration — When the oxidation of food (glucose) takes place in the absence of oxygen, it is called anaerobic respiration. In this process, glucose is not completely oxidized to form carbon dioxide and water. Rather, it is oxidized to produce ethyl alcohol or lactic acid and 2 ATP molecules.

Glucose (in absence of oxygen) ⟶ Carbon dioxide + Ethyl alcohol + Energy (2 ATP)