This is a photo of the lens in an eyeball. If you put the lens onto a piece of paper the letters would turn bigger. This is what the sheep sees when it looks at things.

This is a picture of the iris the surrounds the pupil. The iris is the coloured part in the eye that passes light into the eye. Its actually a ring of mussels that opens and closes to make the pupil bigger and smaller. Making the pupil larger or smaller is also another example of reflect action. The pupil is the black spot in the middle of your eye. In the dark the pupil is as large as it can go so that as much light as possible can enter your eye. In bright light your eye has to be small so that not much light gets in.

The cornea is the curved part in the eye to protect the pupil from getting dirty. Is curved so that light approaching the eye is bent towards the pupil. The cornea is the clear outer skin of your eye. The retina contains special cells called rods and cones. The cones are in charge of the eyes colour vision and the rods are in charge of the black and white vision. At night there is not enough light for the eyes to sense colour.

The optic nerve is the cord at the back of the eye which sends signals from the eye to the brain.