How many redox reactions are involved in glycolysis?

Glycolysis involves two redox reactions. One occurs during the conversion of glyceraldehyde-3-phosphate (G3P) to 1,3-bisphosphoglycerate, where NAD+ is reduced to NADH. The second redox reaction occurs when NADH is oxidized back to NAD+ in fermentation, ensuring the continuity of glycolysis under anaerobic conditions.