Journeys: Nerves. Stop 1
The body's wires
Oh, a mosquito landed on the hand! How does the brain find out? A signal runs along a nerve. Lead it from the hand to the brain!
The signal ran into the spinal cord in the backbone. Now up to the brain!
The brain got the signal and decided to scratch. The order runs back to the hand!
Nerves carry what you feel to the brain, and the brain's orders to the muscles. There and back in a split second!