Although standard redox potentials of NAD+ and NADP+ are essentially the same, and both are capable of carrying high-energy electrons, they are used in very distinct reactions in cells. Explain why NAD+/NADH+H+ is preferentially used for catabolic reaction (e.g. cellular respiration and glucose breakdown) and NADP+/NADPH+H+ is predominantly used for anabolic reaction (e.g. glucose synthesis and carbon fixation) in cells. Make sure you understand the definitions of standard redox potential, catabolism and anabolism.