AP BIOLOGY

Detailed explanation-1: -G-protein-coupled receptors (GPCRs) are the largest and most diverse group of membrane receptors in eukaryotes. These cell surface receptors act like an inbox for messages in the form of light energy, peptides, lipids, sugars, and proteins.

Detailed explanation-2: -Introduction. G protein coupled receptors (GPCRs) are integral membrane proteins that are used by cells to convert extracellular signals into intracellular responses, including responses to hormones, neurotransmitters, as well as responses to vision, olfaction and taste signals.

Detailed explanation-3: -GPCRs possess a heptahelical structure and support normal transmembrane cell signaling processes for growth and cellular development. They are mainly found in eukaryotes but have also been observed in some prokaryotes.

Detailed explanation-4: -Explanation: Rhodopsin is a very stable G-protein coupled receptor.

Detailed explanation-5: -Heterotrimeric. Different types of heterotrimeric G proteins share a common mechanism. They are activated in response to a conformational change in the GPCR, exchanging GDP for GTP, and dissociating in order to activate other proteins in a particular signal transduction pathway.