the pentose phosphate pathway is directly linked to the glycolysis pathway, but it has several unique features in the intermediate metabolism of erythrocytes. which of the following is a major function of the pentose phosphate pathway? a) synthesis of 2,3-bisphosphoglycerate b) Regeneration of ATP c) Production of reduced NADPH d) Production of reduced NADH e) Production of phosphoenolpyruvate f) Production of alanine.