Smelling Smells

In a persons nose is a mucus-covered, twisty cavern that's built to smell as well help a person breath. When a person breaths through their nose air enter through the nostrils. The hairs in the nose act as a filter for things like dirt, dust, pollen etc. Further back in the nose there are small hair like structures called cilia and they sweep back and forth, moving the mucus and everything trapped in it. The air that is being breathed in is nose flows downward. The odor chemicals on the other hand travels upward hitting the ceiling area of the nasal cavity. There are microscopic nerve cells that detect smell. Different smells fit different nerve cells. They fit together like a lock and key. The smells are sent to your brain, and the brain decides if its a good or bad smell.