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 of the following is not true in relation to glycoproteins - \nSelect and explain. \nA. The carbohydrate units of glycoprotein have several repeats, B. Carbohydrate content is same but proteins are different, C. Carbohydrate chain is often linear, D. All of these', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Glycoproteins are proteins to which oligosaccharides are covalently attached.\n\n\n\nThe oligosaccharide chains of glycoproteins lack a serial repeating unit; this is in contrast to the carbohydrate chains in proteoglycans that consists of repeating disaccharide units (amino sugar and acid sugar).\nThe carbohydrate unit of glycoproteins is different and the heterogeneity among glycoproteins is due to the difference in sugar component.\nCarbohydrate chain is often branched in glycoproteins.', 'role': 'assistant'}]