Rocket is building a cardboard castle in the den when a warm, toasty smell drifts in.
He sniffs. He drops his tape. In three seconds he is standing in the kitchen doorway.
"Toast is ready!" Raven laughs. "How did you know? Nobody called you."
"My nose told me," Rocket says.
"What do you notice about everything that happened between the smell and your feet moving?" Raven asks.
Nova hovers by the toaster. "Here is my hint," she says. "Something had to carry the message. Something had to decide."
Animals, including people, take in information with their senses: seeing, hearing, smelling, tasting and touching.
Special cells in your senses detect light, sound, smells, tastes, pressure and heat.
Nerves carry messages from those senses to the brain. The brain makes sense of the information.
Then the brain sends messages through nerves to your muscles. You respond, which means you act.
Nerves carry two kinds of messages.
Some carry information in, from your senses to your brain.
Others carry orders out, from your brain to your muscles.
Both kinds work together every time you respond.
| Statement | True or false? |
|---|---|
| Smelling is one of the senses. | ? |
| Nerves carry messages to the brain. | ? |
| Muscles make sense of smells. | ? |
| Special cells in your senses can detect heat. | ? |
Great start, signal scientist! Tomorrow we look at eyes and ears, and meet an amazing listener.