This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'All of the following serve as intracellular second messengers in receptor-mediated signal transduction except \nSelect and explain. \nA. CyclicAMP, B. Inositoltrisphosphate, C. Diacylglycerols, D. G proteins', 'role': 'user'}, {'content': 'Answer: D \nExplanation: GPCR do not act as intracellular messengers thery are receptors present on the trans membranes of the cell and help in ligand binding and cell signalling different secondary messengers include cAMP, IP3/DAG,cGMP and some times calcium. Ref: KDT 6/e pg. 39', 'role': 'assistant'}]