AP BIOLOGY

Detailed explanation-1: -So, the correct answer is oxygen.

Detailed explanation-2: -Oxygen is the final electron acceptor in this respiratory cascade, and its reduction to water is used as a vehicle by which to clear the mitochondrial chain of low-energy, spent electrons.

Detailed explanation-3: -Cytochrome c oxidase complex, the last complex in the chain comprises of cytochrome a and cytochrome a3. Cytochrome a3 possesses copper that helps transfer electrons to oxygen. Oxygen is the ultimate electron acceptor wherein it becomes reactive and combines with protons to form metabolic water.

Detailed explanation-4: -The final electron acceptor is oxygen (O2), it has a high electronegativity and accepts low-energy electrons. Hydrogen is combined with oxygen, forming water as the final product.

Detailed explanation-5: -Answer and Explanation: The final electron acceptor of the electron transport chain of oxidative phosphorylation is oxygen. Oxygen accepts electrons and combine with protons to form water, a by-product of cellular respiration.