This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Physiology
[{'content': 'Because free ammonia in the blood is toxic to the body, it is transported in which of the following non-toxic forms? \nSelect and explain. \nA. Histidine and urea, B. Phenylalanine and methionine, C. Glutamine and urea, D. Lysine and glutamine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. Glutamine and ureaBoth urea and glutamine play an important role in the storage and transport of ammonia in the blood. Histidine, phenylalanine, methionine, and lysine are not involved in ammonia transport.', 'role': 'assistant'}]