This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carbohydrates, Subject name: Biochemistry
[{'content': 'Sodium fluoride is a good in-vitro preservative of glucose in blood samples because it inhibits: \nSelect and explain. \nA. Enolase, B. Hexokinase, C. Phosphofructokinase, D. Pyruvate dehydrogenase', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. (a) EnolaseRef: Harper's Biochemistry, 30 edn. pg. 170-171th* Enolase, also known as phosphopyruvate hydratase, is a metallo-enzyme responsible for the catalysis of the conversion of 2-phosphoglycerate to phosphoenol pyruvate, the ninth and penultimate step of glycolysis.* If the sample for blood glucose is kept for some time, the Red blood cells will start consuming the sugar available and hence the final report shall be lower than actual.* Sodium flouride shall inhibit enolase and ensure an accurate result.", 'role': 'assistant'}]