What is a G-Protein Receptor with GTP Bound to It

Question

What is a G-protein receptor with GTP bound to it?
A)It is in its active state.
B)It is signalling a protein to maintain its shape and conformation.
C)It is using cGMP as a second messenger.
D)It is directly affecting gene expression.
E)It is non-functional.

Accepted Answer

G-protein receptors are activated by binding of ligands, which in turn leads to binding of GTP to the receptor. The binding of GTP causes a conformational change in the receptor, leading to activation of downstream signaling pathways. Therefore, a G-protein receptor with bound GTP is in its active state.