What is the function of NAD in glycolysis?

NAD+ serves as an electron carrier in glycolysis. During the oxidation of glyceraldehyde-3-phosphate (G3P) to 1,3-bisphosphoglycerate, NAD+ is reduced to NADH by accepting electrons. NADH then carries the high-energy electrons to the electron transport chain (in aerobic conditions) or to fermentation pathways (in anaerobic conditions) to regenerate NAD+ and allow glycolysis to continue.