This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
Second messengers, DAG and IP3 are formed from 
Select and explain. 
A. Phosphatidyl choline, B. Phosphatidyl ethanolamine, C. Phosphatidyl serine, D. Phosphatidyl inositol
D: Phosphatidyl inositol
Answer: D: Phosphatidyl inositol 
Explanation: Phosphatidylinositol Is a Precursor of Second MessengersThe G proteins activate phospholipase C, which hydrolyzes phosphatidylinositol4,5-bisphosphate to produce diacylglycerols and the water-soluble second messenger inositol 1,4,5-triphosphate (IP3).Ref: Harper&;s Biochemistry; 30th edition; Chapter 54; White Blood Cells