e. they phosphorylate proteins -this is not true.
G proteins are specialized proteins with the ability to bind the nucleotides guanosine triphosphate (GTP) and guanosine diphosphate (GDP). A G protein alpha subunit binds either GTP or GDP depending on whether the protein is active (GTP) or inactive (GDP).
G proteins work like a switch — turned on or off by signal-receptor interactions on the cell's surface.
A G proteins are controlled by GEFs which catalyse the sequential release and binding of guanine nucleotides, and by GTPase activity.
G proteins help amplify hormones signal.
G proteins act as second messenger and thus they amplify hormone signals.
they do not phosphorylate proteins. This work is performed by the kinase present in the cell.
Dear Yunzila Iftikhar, You're always welcome!
thank you so much..