During the reduction of NAD+, what is produced?

During the reduction of NAD+, NADH is produced as a result of the addition of electrons and protons to NAD+. This process is essential in cellular respiration and various metabolic pathways. When NAD+ accepts two electrons and one proton (a hydride ion), it becomes reduced to NADH.

NADH then plays a critical role as an electron carrier in the electron transport chain, which is a key component of aerobic respiration. By transferring electrons, NADH helps to drive the production of ATP, the energy currency of the cell. This reduction process is fundamental to how living organisms extract energy from glucose and other substrates.

In contrast, glucose is a substrate that can be broken down to generate energy, ATP is a product of energy conversion processes but is not produced directly during the reduction of NAD+, and water is formed in different biochemical reactions, primarily related to oxidative phosphorylation, but not during the reduction of NAD+.