This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Physiology
Transducin is required for 
Select and explain. 
A. Smell, B. Hearing, C. Taste, D. Vision
D: Vision
Answer: D: Vision 
Explanation: Ans. (d) Vision(Ref: Ganong, 25th ed/p. 178)The G protein coupled receptor in rods is called "Transducin''Role of transducin is to activate the enzyme phosphodiesterase that degrades cGMP