Final answer:
The main structural difference between NaD+/NADH and NADP+/NADPH is the presence of an additional phosphate group in NADP+/NADPH. Functionally, NADH and NADPH carry electrons and hydrogen atoms in oxidative reactions, while in reductive reactions, they give up electrons and H+.
Step-by-step explanation:
The main structural difference between NAD+/NADH and NADP+/NADPH is the presence of an additional phosphate group in NADP+/NADPH. NAD+ and NADH are involved in energy extraction from sugars and play a role in cellular respiration, while NADP+ and NADPH are important in photosynthesis and anabolic reactions.
Functionally, NADH and NADPH carry electrons and hydrogen atoms in oxidative reactions, while in reductive reactions, they give up electrons and H+. NAD+ and NADP+ act as electron acceptors and can be reduced to NADH and NADPH, respectively, which can then be oxidized back to NAD+ and NADP+.