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': 'Triacylglycerol and Cholesteryl ester are \nSelect and explain. \nA. Non polar lipids, B. Polar lipids, C. Amphipathic lipids, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In general, lipids are insoluble in water since they contain a predominance of non polar (hydrocarbon) groups. However, fatty acids, phospholipids, sphingolipids, bile salts, and to a lesser extent, cholesterol contain polar groups. Therefore, a part of the molecule is hydrophobic, or water insoluble; and a part is hydrophilic, or water. Such molecules are described as amphipathic. Water interfaces with the polar group in the water phase and the non polar group in the oil phase. A bilayer of such amphipathic lipids is the basic.', 'role': 'assistant'}]