<span><span>The carboxyl end of the G- protein-coupled receptor (GPCR) is located in the cytosol (it is intracellular). Carboxyl terminus is one of the most variable structures of the protein. All of the GPCR are </span><span>structural and functional similar, unlike their ligands.</span></span>
The ones about enzymes are chemical digestion and the ones about chewing are mechanical digestion.
A) be unable to maintain homeostasis