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
First step in synthesis of eicosanoids is? 
Select and explain. 
A. Activation of lipooxygenase, B. Activation of PGH2 synthetase, C. Activation of hydrolase, D. None
C: Activation of hydrolase
Answer: C: Activation of hydrolase 
Explanation: Eicosanoids synthesis is governed by the rate of release of arachidonic acid from membrane lipids in response to appropriate stimuli. These stimuli activate hydrolases, including phospholipase A , which conves arachidonic acid into Prostaglandins, thromboxanes by the COX pathway or Leukotrienes and lipoxins by the LOX pathway Reference: Harpers illustrated biochemistry 31st edition Page no 224