NAD+ and NADPH both partake and catalyze reactions for two-electron transfers. However, they each have specialized metabolic roles; NAD+ is used in oxidations in catabolic reactions whereas NADPH is used in anabolic reductions. What biological conditions cause this distinction? The study of these oxidation-reduction reactions is crucial to understanding the metabolic pathways in biochemistry. What property does this set of redox molecules possess that allow biochemists to assay reactions involving these coenzymes (what techniques can be employed to monitor the oxidation-reduction character of these species)