This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'When an enzyme is competitively inhibited, which of the following changes occur? \nSelect and explain. \nA. The apparent Km is unchanged., B. The apparent Km is decreased., C. Vmax is decreased., D. Vmax is unchanged.', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Features of noncompetitive inhibition:\n\nInhibitor have no structural resemblance to substrate.\nMost irreversible (Except a few reversible non-competitive inhibition).\nExcess substrate do not abolish the inhibition.\nKm remains the same.\nVmax decreases.\n\n\xa0\nFeatures of competitive inhibition:\n\nInhibitor will be structural analogue of substrate.\nReversible\xa0\nExcess substrate abolish the inhibition.\nKm increases.\nVmax remains the same.', 'role': 'assistant'}]