context: G protein coupled receptor (GPCR) Another name is called the 7-transmembrane receptor (7TMR). As can be seen from the name, as seen in [Fig. 1], its structure is a structure that spans the cytoplasmic surface and the outer surface of the cell membrane or the cell membrane of an organ within the cell and passes through the membrane 7 times. There are about 800 ~ 1000 receptor types in vivo, and catalyzes almost all physiological reactions in vivo. This type is largely divided into 5 types (type A, B, C, D, E, F), and type A include Rhodopsin, which senses light, postsensory receptor, which senses odor, and adrenaline receptor, which detects adrenaline or noradrenaline. It is known that Type B contains peptide receptors, and Type C contains glutamate receptors and numb receptors. At this time, the substance attached to the receptor is defined as a ligand, and the ligand is divided into a receptor agonist that promotes the reaction of the receptor and a receptor antagonist that does not promote the reaction.
question: What is the function of G protein?
answers.text: catalyzes almost all physiological reactions in vivo.