You drift upward from piece of freshly cut fruit. Life is peaceful until WHOOSH—you're sucked into a giant kid's nose! You smash into the thick mucus at the top of the nasal cavity. This is not your day. Slowly, hair-like projections, called cilia, sweep you towards the receptor areas of a nerve cell looming in the distance. What a day to be a molecule!

Molecules enter your nose when you breathe in. When the ones that "smell" pass through the layer of thick mucus, they excite nerve cells.