<prompt> Which of the enzyme of glycolysis is a pa ofgluconeogenesis ?Pyruvate kinasePFKHexokinasePhosphoglycerate kinase  <response>: Ans. is d i.e., Phosphoglycerate kinase Seven of the reactions of glycolysis are reversible and are used in the synthesis of glucose by gluconeogenesis. Thus, seven enzymes are common to both glycolysis and gluconeogenesis: i Phosphohexose isomerase; ii Aldolase; iii Phosphotriose isomerase, iv Glyceraldehyde 3-phosphate dehydrogenase; v Phosphoglycerate kinase; vi Phosphoglycerate mutase; vii Enolase. Three reactions of glycolysis are irreversible which are circumvented in gluconeogenesis by four reactions. So, enzymes at these steps are different in glycolysis and gluconeogenesis. Reactions Enzyme in glycolysis Enzyme in gluconeogenesis Glucose - Glucose-6-P Hexokinaseglucokinase Glucose-6-phosphatase Fructose-6-P - Fructose- I ,6-BP Phosphofructokinase Fructose-1-6-bisphosphatase Phosphoenolpyruvate - Pyruvate Pyruvate kinase Pyruvate carboxylase PEP carboxykinase 