Is NAD+ an oxidizing agent or reducing agent?

Is NAD+ an oxidizing agent or reducing agent?

• A. Oxidizing agent
• B. Reducing agent
• C. Catalyst
• D. Buffer

Answer: (A)

NAD+ acts as an oxidizing agent because it takes electrons from other molecules. In redox reactions, an oxidizing agent is the substance that accepts electrons; NAD+ accepts two electrons and a proton to become NADH, while the molecule that donated the electrons becomes oxidized. This is seen in many metabolic steps, such as glycolysis, where NAD+ is reduced to NADH by the substrate. NADH, in turn, can donate electrons to other acceptors and is thus the reducing agent. The other options don’t fit: a catalyst speeds reactions without being consumed, and a buffer resists pH changes.

NAD+ acts as an oxidizing agent because it takes electrons from other molecules. In redox reactions, an oxidizing agent is the substance that accepts electrons; NAD+ accepts two electrons and a proton to become NADH, while the molecule that donated the electrons becomes oxidized. This is seen in many metabolic steps, such as glycolysis, where NAD+ is reduced to NADH by the substrate. NADH, in turn, can donate electrons to other acceptors and is thus the reducing agent. The other options don’t fit: a catalyst speeds reactions without being consumed, and a buffer resists pH changes.