Why is Oxygen Needed in Cellular Respiration

Question

Why is oxygen needed in cellular respiration?
A) Oxygen combines with ADP to create ATP.
B) Oxygen is the final electron acceptor in the electron transport chain.
C) Oxygen carries electrons from the citric acid cycle to the electron transport chain.
D) Fermentation in muscle cells relies upon oxygen as an electron acceptor.

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.