What is the primary function of the electron transport chain (ETC) in cellular respiration?

• A. To produce ATP by transferring electrons through a series of proteins
• B. To fix carbon dioxide into organic molecules
• C. To break down glucose into pyruvate
• D. To synthesize proteins from amino acids

Answer: (A)

Verified step by step guidance

1. Understand that cellular respiration is a process that cells use to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.
2. Recognize that the electron transport chain (ETC) is the final stage of cellular respiration, occurring in the inner mitochondrial membrane.
3. Identify that the primary function of the ETC is to transfer electrons from electron donors like NADH and FADH2 to electron acceptors such as oxygen, through a series of protein complexes.
4. Acknowledge that as electrons move through these protein complexes, protons (H+) are pumped across the mitochondrial membrane, creating a proton gradient.
5. Understand that this proton gradient is used by ATP synthase to produce ATP from ADP and inorganic phosphate, a process known as oxidative phosphorylation.