Final answer:
The reactants in the energy payoff phase of glycolysis are 2 Glyceraldehyde-3-phosphate, 4 ADP, 2 Pi, and 2 NAD+. This phase produces 4 ATP and 2 NADH with a net gain of two ATP.Glycolysis energy payoff: 2 G3P yield 4 ATP, 2 NADH, consuming 4 ADP, 2 Pi, net gain 2 ATP.
Step-by-step explanation:
During the energy payoff phase of glycolysis, the reactants are 2 Glyceraldehyde-3-phosphate (G3P), 4 ADP, 2 Pi (inorganic phosphate), and 2 NAD+. In this phase, each G3P is converted by the enzyme glyceraldehyde-3-phosphate dehydrogenase into 1,3-bisphosphoglycerate, which involves the oxidation of G3P and the reduction of NAD+ to NADH. Subsequently, 1,3-bisphosphoglycerate transfers a phosphate to ADP to form ATP and 3-phosphoglycerate. This results in the production of 4 ATP molecules and 2 NADH molecules, with a net gain of two ATP molecules considering that two ATP were used during the energy investment phase of glycolysis.
In the energy payoff phase of glycolysis, two molecules of glyceraldehyde-3-phosphate undergo reactions, yielding four ATP molecules and two NADH molecules. Four molecules of ADP and two molecules of inorganic phosphate (Pi) are consumed. This results in the net production of two ATP molecules. The process involves substrate-level phosphorylation, where high-energy phosphate groups are transferred to ADP, forming ATP. Additionally, two molecules of NAD+ are reduced to form two NADH molecules. This phase marks a crucial step in extracting energy from glucose during cellular respiration.