This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Proteins and Amino Acids, Subject name: Biochemistry
[{'content': 'Which one of the following can be homologous substitution for isoleucine in a protein in sequence? \nSelect and explain. \nA. Methionine, B. Aspartic acid, C. Valine, D. Arginine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. ValineConservative SubstitutionOne amino acid replaced by another amino acid of similar characteristicsExamples of homologous substitution is shown in the given table below.Hydrophilic, AcidicAspGlu Hydrophilic, BasicHisArgLys Polar, UnchargedSerThrGlnAsn HydrophobicAlaPheLeuIleValProNonconservative (Nonhomologous) SubstitutionOne amino acid replaced by another amino acid of different characteristics', 'role': 'assistant'}]