AP BIOLOGY

Detailed explanation-1: -G protein-coupled receptor (GPCR), also called seven-transmembrane receptor or heptahelical receptor, protein located in the cell membrane that binds extracellular substances and transmits signals from these substances to an intracellular molecule called a G protein (guanine nucleotide-binding protein).

Detailed explanation-2: -GPCRs are membrane-bound proteins that have seven membrane-spanning domains connected by intracellular and extracellular domains. In the inactive conformation, the a-subunit of the G protein binds to GDP and is bound to a beta-gamma complex (a).

Detailed explanation-3: -G protein-coupled receptors, or GPCRs, also known as 7-Transmembrane receptors (7-TM receptors), are integral membrane proteins that contain seven membrane-spanning helices. As the name suggests they are coupled to heterotrimeric G proteins on the intracellular side of the membrane.

Detailed explanation-4: -Canonical GPCR architecture consists of three functional domains (Box 1), a TM domain (TMD) that links the intracellular domain (ICD) to the extracellular domain (ECD) [13]. The ICD recruits G-proteins and other signaling molecules to exert a specific intracellular effect.

Detailed explanation-5: -GPCRs are integral membrane proteins that possess seven membrane-spanning domains or transmembrane helices. The extracellular parts of the receptor can be glycosylated.