Which of the following best describes the role of oxygen in aerobic respiration?

Which of the following best describes the role of oxygen in aerobic respiration?

• A. It is a byproduct of glucose breakdown
• B. It acts as the final electron acceptor in the electron transport chain
• C. It is unnecessary for ATP production
• D. It inhibits the process of respiration

Answer: (B)

The role of oxygen in aerobic respiration is best described by its function as the final electron acceptor in the electron transport chain. During aerobic respiration, glucose is broken down through a series of metabolic processes, primarily glycolysis, the Krebs cycle, and oxidative phosphorylation. In the electron transport chain, which takes place in the inner mitochondrial membrane, electrons derived from the oxidation of nutrients are passed through a series of protein complexes. Oxygen plays a crucial role at the end of this chain, combining with electrons and protons to form water. This process is vital because it allows the electron transport chain to continue functioning efficiently. The flow of electrons down the chain drives the pumping of protons across the membrane, creating a proton gradient that is used by ATP synthase to generate ATP. Without oxygen, the electron transport chain would cease to operate, leading to a significant reduction in ATP production. Thus, oxygen is essential for maximizing energy yield in aerobic respiration.

The role of oxygen in aerobic respiration is best described by its function as the final electron acceptor in the electron transport chain. During aerobic respiration, glucose is broken down through a series of metabolic processes, primarily glycolysis, the Krebs cycle, and oxidative phosphorylation. In the electron transport chain, which takes place in the inner mitochondrial membrane, electrons derived from the oxidation of nutrients are passed through a series of protein complexes.

Oxygen plays a crucial role at the end of this chain, combining with electrons and protons to form water. This process is vital because it allows the electron transport chain to continue functioning efficiently. The flow of electrons down the chain drives the pumping of protons across the membrane, creating a proton gradient that is used by ATP synthase to generate ATP. Without oxygen, the electron transport chain would cease to operate, leading to a significant reduction in ATP production. Thus, oxygen is essential for maximizing energy yield in aerobic respiration.