G-protein-coupled receptors (GPCRs) all have a similar struc…

G-protein-coupled receptors (GPCRs) all have a similar structure with ____________ transmembrane domains. When a GPCR binds an extracellular signal, an intracellular G protein, composed of _________ subunits, becomes activated. When unstimulated, the α subunit is bound to ________, which is exchanged for _______ upon stimulation. The intrinsic ________ activity of the α subunit is important for inactivating the G protein, as can be _________ proteins. The α subunits come in different types, for example, Gαs subunits typically activate an effector protein to increase intracellular _______.   Each matched value will only be used once.   guanylyl cyclase            GTPase          adenylyl cyclase phospholipase C           phosphodiesterase      RGS seven                             three               two       ATP GDP                              cAMP              GTP       Ca2+