This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Enzyme Kinetics, Subject name: Biochemistry
[{'content': 'Enzyme activity is expressed as: (PGI Dec 2006) \nSelect and explain. \nA. Millimoles/lit, B. Mg/lit, C. Mg/dl, D. Micromoles/min', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans: D (Micromoles/min) Enzme activity is expressed as micromoles of substrate converted to product per minute^ under optical condition of measurement. One standard unit {or international unit) of enzyme activity (U) is that activity which catalyses transformation of 1 micromole of substrate per minute.Modern method of enzyme activity is in katals (Kat)1 Kat=Conversion of 1 mole of substrate per second.', 'role': 'assistant'}]