What is the role of oxygen in cellular respiration?

Oxygen plays a critical role in cellular respiration, which is the process by which cells generate energy from glucose. In cellular respiration, glucose is broken down in the presence of oxygen to produce ATP (adenosine triphosphate), which is the primary energy source for cells.

The process of cellular respiration consists of three main stages: glycolysis, the citric acid cycle (also known as the Krebs cycle), and the electron transport chain. In the first stage, glucose is broken down into pyruvate through glycolysis. Then, in the citric acid cycle, pyruvate is further broken down to produce more ATP. Finally, in the electron transport chain, oxygen is used as the final electron acceptor to generate even more ATP.

Without oxygen, cells would not be able to produce ATP efficiently through cellular respiration. This is why oxygen is known as the final electron acceptor in aerobic respiration. In the absence of oxygen, cells can still produce ATP through a process called anaerobic respiration, but it is much less efficient and can lead to the accumulation of lactic acid or other byproducts.