EVERYDAY SCIENCE

Detailed explanation-1: -In terrestrial vertebrates, including humans, the receptors are located on olfactory receptor cells, which are present in very large numbers (millions) and are clustered within a small area in the back of the nasal cavity, forming an olfactory epithelium.

Detailed explanation-2: -The initial event in odor perception is the detection of odorants by olfactory (odorant) receptors (ORs), which are located on olfactory sensory neurons in the olfactory epithelium of the nose (1–4).

Detailed explanation-3: -The olfactory receptors are situated in the mucous membrane of the nasal cavity. The nerve fibers synapse with other cells in the olfactory bulb and finally end in the olfactory areas of the cerebral cortex, the periamygdaloid and prepiriform areas.

Detailed explanation-4: -The olfactory epithelium is a thin, cellular tissue that runs along the roof of the nasal cavity. In adults, it is situated about 7 centimeters (cm) behind the nostrils. It is part of the nasal septum and the superior turbinate bones. Three cell types make up the olfactory epithelium: basal, supporting, and olfactory.