This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of lipid, Subject name: Biochemistry
[{'content': 'Arachidonic acid is synthesized from \nSelect and explain. \nA. Stearic acid, B. Linoleic acid, C. Linolenic acid, D. Oleic acid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Essential Fatty Acids (EFA) Normal dietary allowance of PUFA is 2-3% of total calories. Linoleic acid (o6, 18C, D 9,12) and linolenic acid (o3, 18C, D 9,12,15) are the only fatty acids which cannot be synthesized in the body. They have to be provided in the food; hence they are essential fatty acids. Arachidonic acid can be formed if the dietary supply of linoleic acid is sufficient PUFA may be formed from monounsaturated fatty acids by the introduction of double bonds only between an existing double bond and carboxyl end of the fatty acid (but not between the omega end and an existing double bond). Hence linoleic acid cannot be synthesized from oleic acid. However, linoleic acid can be conveed to arachidonic acidRef: DM Vasudevan - Textbook of Biochemistry, 6th Edition, page no: 162', 'role': 'assistant'}]