GPCR is composed of seven transmembrane alpha helices, an extracellular amino terminus, three extracellular loops, three intracellular loops, and an intracellular carboxyl terminus. The seven transmembrane alpha helices are connected by the three intracellular loops, the three extracellular loops, and the intracellular carboxyl terminus. The function of the N-terminus of the GPCR is to stabilize the first transmembrane helix to ensure proper receptor structure. This is essential for ligand binding, receptor internalization, and integration into the cell membrane. The C-terminus of the cell plays a vital role in interacting with intracellular proteins such as G proteins and arrestins. The GPCR is arranged as a tertiary structure, resembling a barrel shape. The seven transmembrane proteins produce a cavity within the plasma membrane that acts as a ligand-binding domain.