During cellular respiration, what is the role of NAD+?

NAD+ plays a crucial role in cellular respiration by acting as an electron carrier. It is involved in redox reactions, particularly during the breakdown of glucose. When glucose is metabolized, it loses hydrogen atoms. NAD+ accepts these hydrogen atoms along with their electrons, becoming NADH in the process. This conversion is essential because NADH then carries the high-energy electrons to the electron transport chain, where they are used to produce ATP—the main energy currency of the cell.

In this way, NAD+ helps facilitate the transfer of energy during cellular respiration without providing energy directly. Unlike providing glucose or synthesizing DNA, which are separate processes, or directly generating energy, the primary purpose of NAD+ revolves around its ability to transport electrons and support the energy-producing pathways within the cell. This function is vital for efficient ATP production during aerobic respiration.