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': 'Which is involved in transpo of long chain acyl-CoA in mitochondria? \nSelect and explain. \nA. Ornithine, B. Xanthine, C. Carnitine, D. Albumin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In humans carnitine is synthesized from protein-derived trimethyllysine in liver, brain and kidney.Muscles take up carnitine from the blood in an exchange-diffusion process with endogenous deoxycarnitine, the immediate precursor of carnitine.Besides catalysing the transpo of long-chain acyl groups in mitochondria, carnitine is necessary for the expo of intramitochondrially produced sho-chain acyl residues and for the trapping and the elimination of unphysiological compounds (benzoic, pivalic, valproic acids etc.).', 'role': 'assistant'}]