The term olfactory zone (OLZ) refers to a small area of olfactory epithelium (OLE) where activation of olfactory receptors (OLR) sensitive to different combinations of oderant molecules give rise to different smells. One combination may produce a "fresh, rose, oily floral" smell; another may produce a "rancid, sour goat-like" smell. Every OLR responds to a unique one of some 400 different oderant molecules. Some oderants stimulate a large number of OLRs, others to only one or a selective few. OLRs sensitive to certain combinations are located in different OLZs. Thus, activation of different OLZs results in one's perception of different complex smells ( Buck-2013 ). Updated 15 Jan 2025.