Humber Admissions Practice Test

Aerobic respiration is a biological process in which organisms convert glucose and oxygen into carbon dioxide, water, and energy in the form of ATP. Oxygen is a critical reactant in this process, allowing cells to efficiently extract energy from glucose through a series of metabolic pathways, including glycolysis, the Krebs cycle, and the electron transport chain.

In the presence of oxygen, aerobic respiration yields significantly more energy—up to 36-38 ATP molecules per glucose molecule—compared to anaerobic pathways, which occur in the absence of oxygen and generate much less energy. Therefore, the requirement for oxygen is essential in facilitating the complete oxidation of glucose, making it the indispensable component for aerobic respiration to occur.