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
Prostaglandins are derived from: 
Select and explain. 
A. Stearic acid, B. Arachidonic acid, C. Glutamic acid, D. Aspartic acid
B: Arachidonic acid
Answer: B: Arachidonic acid 
Explanation: Ans. (b) Arachidonic acidRef: Lippincott's Biochemistry, 6th ed. P 213* Prostaglandin is derived from the metabolism of arachidonic acid with the help of cyclooxygenase (COX) enzyme.