Rocket builds a camera box with a peephole. "My box catches light," he says. "But it does not know what it sees!"
Raven tilts her head. "What do you notice? What does your eye have that the box does not?"
Nova points her beam at the back of Rocket's head. "Follow the message," she says. "Where does it go next?"
Rods and cones turn light into signals.
The optic nerve carries those signals from the eye to the brain.
Think of it as a fast message line between the eye and the brain.
A part at the back of the brain handles what the eyes send.
The brain turns the signals into the pictures you see.
Then you know it is a cat, an apple or a bike!
Above the outer corner of each eye is a gland that makes tears.
Each time you blink, a little tear fluid comes out of your upper eyelid.
Tears wash away dust and germs. They keep the eye from drying out.
You can help your eyes too. Wear goggles for messy science projects.
Wear sunglasses in bright sun. And never look straight at the Sun.
| Statement | True or false? |
|---|---|
| The optic nerve carries signals to the brain. | ? |
| The eye can make a picture without the brain. | ? |
| Blinking brings out a little tear fluid. | ? |
| It is safe to stare at the Sun for a short time. | ? |
Amazing explaining! Tomorrow is Body Lab Day. You will watch your pupils change size.