Which of the following best describes the function of ion channels compared to G protein-coupled receptors?

• A. Ion channels allow ions to pass through the membrane, while G protein-coupled receptors activate intracellular signaling pathways.
• B. Ion channels activate G proteins, while G protein-coupled receptors synthesize signaling molecules.
• C. Ion channels synthesize signaling molecules, while G protein-coupled receptors allow ions to pass through the membrane.
• D. Both ion channels and G protein-coupled receptors require ATP to function.

Answer: (A)