The Eye

Have you ever wondered how the eye works? The human eye is about as big as a ping pong ball. It sits in the eye socket inside the skull. The eyelid protects the front part of the eye. The eyelid is a piece of skin that is movable so that it can open and close. The eyelid also helps keep the eye moist. It does this by blinking. Blinking is a voluntary and involuntary action. The eye blinks involuntarily several times a minute.

The eyelid also has great reflexes. This is a form of protection for the eye. If a ball or other object is coming towards the eye, the eyelid will quickly close to protect the eye. The eyelid will also close or squint when there is bright sunlight. The eyelashes are another important protection for the eye. Eyelashes keep dirt and other particles from getting into the eyes.

The white part of the eyeball is called the sclera. The sclera is the outside coating of the eyeball. Tiny blood vessels line the sclera. The cornea rests directly on top of the colored part of the eye. The cornea is completely transparent so that light can filter through. Behind the cornea are the iris and the pupil. The iris is the colorful part of the eye. The pupil determines how much light is allowed into the eye. The eye is an amazing part of the body.