Final answer:
NAD+ is a coenzyme involved in oxidation-reduction reactions. It acts as an electron acceptor and can be easily reduced to NADH. NAD+ is derived from vitamin B3 and is important in cellular metabolism.
Step-by-step explanation:
Nicotinamide adenine dinucleotide (NAD+) is a coenzyme that is involved in many oxidation-reduction reactions in living organisms. It functions as an electron acceptor and can be easily reduced to its reduced form, NADH, by accepting two electrons and a proton. NAD+ is derived from vitamin B3 (niacin) and plays a crucial role in cellular metabolism.