How do we taste and smell:
Our tongue is covered with thousands of taste receptors (also called taste buds). These are grouped together in special areas on our tongue. So we taste sweetness at the front, bitterness at the back, and sourness and saltiness at the side of our tongue. Also we have smell receptors (or scent receptors) in our nose. So we sniff, tiny particles in the air are carried to these smell receptors. Then the taste and smell receptors send messages (or signals) to our brain.