If an animal cell suddenly lost the ability to produce GTP, what might happen to its signaling system?
A. It could activate only the epinephrine system.
B. It would not be able to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
C. It would be able to carry out reception and transduction but would not be able to respond to a signal.
D. It would use ATP instead of GTP to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
E. It would employ a transduction pathway directly from an external messenger.
Answer: B