This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharmacodynamics, Subject name: Pharmacology
PI P2 is cleaved into IP3 and DAG by - 
Select and explain. 
A. Protein kinase'C', B. Phospholipase, C. cAMP, D. Caspases
B: Phospholipase
Answer: B: Phospholipase 
Explanation: Ans. is 'b' i.e., Phospholipase o Activation of phospholipase (by stimulatory G protein) hydrolyses the membrane phospholipid phosphatidyl inositol 4, 5 bisphosphate (PIP2) to generate the second messenger inositol 1, 4, 5 - triphosphate (IP3) and diacylglycerol (DAG).o IP3 mobilizes Ca+2 from intracellular organelles - increased cytosolic Ca+2.o DAG enhances Protein Kinase 'c' activation by Ca+2.o Ca+2 acts as third messenger in this type of transduce mechanism and mediates the physiological effects of drugs.