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': 'Aminoacyl t-RNA is required for all except - \nSelect and explain. \nA. Hydroxyproline, B. Methionine, C. Cystine, D. Lysine', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Hydroxyproline and hydroxylysine are not represented into genetic code, i.e. they to not have t-RNA capable of accepting them and inserting them into polypeptide chain. Therefore, they have to be synthesized post-translationally from proline and lysine residues in the polypeptides.', 'role': 'assistant'}]