Why is oxygen needed in cellular respiration?

Question

Quizplus · Accepted Answer

Oxygen is the final electron acceptor in the electron transport chain, which is the last step in cellular respiration. This process generates a large amount of ATP, the energy currency of cells. Without oxygen, electron transport is disrupted, and the cell cannot produce ATP efficiently.

Note: Choices A, C, and D are incorrect. In choice A, oxygen is not directly involved in the process of creating ATP from ADP. In choice C, oxygen is not a carrier of electrons from the citric acid cycle, but rather accepts electrons from the electron carriers NADH and FADH2. In choice D, fermentation does not rely on oxygen as an electron acceptor, but rather uses other molecules such as pyruvate or acetaldehyde.

Why Is Oxygen Needed in Cellular Respiration