Smelling

Smelling
Smells come from chemicals that flat in the air. Your nose picks up smells when you breathe in. Your sense of smell can help you to find out about the world around you. Smells are invisible and can let you know about things you cannot see.

1. Smelly things give off chemicals that travel through the air. As you breathe in, some of the chemicals get trapped in for a while in the slimy mucus inside your nose.
2. Your smell detector cells are in a small patch under the mucus. These cells send messages to your brain about the chemicals that are trapped in the mucus. Smell detectors can recognize about 3,000 different chemicals.
3. Most smells are made up of a mixture of chemicals. You can learn to recognize many thousands more of these mixtures.