Question

How do we sense smell ?

Answer 1

Humans detect smells by inhaling air that contains odor molecules, which then bind to receptors inside the nose, relaying messages to the brain. Most scents are composed of many odorants; a whiff of chocolate, for example, is made up of hundreds of different odor molecules.
Underneath the mucus, in the olfactory epithelium, specialized receptor cells called olfactory receptor neurons detect the odor. These neurons are capable ofdetecting thousands of different odors. The olfactory receptor neurons transmit the information to the olfactory bulbs, which are located at the back of the nose.