<P> Overall Reaction: </P> <P>--- Glucose + 6 O2 → 6 Carbon Dioxide + 6 Water + 36 ATPs </P> <P> Glycolysis is a metabolic pathway that takes place in the cytosol of cells in all living organisms . This pathway can function with or without the presence of oxygen . In humans, aerobic conditions produce pyruvate and anaerobic conditions produce lactate . In aerobic conditions, the process converts one molecule of glucose into two molecules of pyruvate (pyruvic acid), generating energy in the form of two net molecules of ATP . Four molecules of ATP per glucose are actually produced, however, two are consumed as part of the preparatory phase . The initial phosphorylation of glucose is required to increase the reactivity (decrease its stability) in order for the molecule to be cleaved into two pyruvate molecules by the enzyme aldolase . During the pay - off phase of glycolysis, four phosphate groups are transferred to ADP by substrate - level phosphorylation to make four ATP, and two NADH are produced when the pyruvate are oxidized . The overall reaction can be expressed this way: </P> <Dl> <Dd> Glucose + 2 NAD + 2 P + 2 ADP → 2 pyruvate + 2 NADH + 2 ATP + 2 H + 2 H O + heat </Dd> </Dl>

During cell respiration the most atp are produced by the electron transport chain