The Parts of the Eye: How It Works, Explained Simply

Video Transcript

The eye is about the size of a ping pong ball, and every part of it has a job. At the front is the cornea, a clear dome with no blood vessels at all. It protects the eye and provides most of its focusing power. Around the rest of the eye is the sclera, the tough white outer wall that holds the eye's shape. The coloured iris sits behind the cornea. Its opening is the pupil, which widens in dim light and narrows in bright light. Just behind the pupil is the clear lens, suspended by fine fibres from the ciliary body, the ring of muscle that changes its shape. The large space behind the lens is filled with the vitreous, a clear jelly that gives the eye its volume. Lining the back wall is the retina. At its centre is the macula, responsible for your sharpest detail, and off to one side is the optic disc, where the optic nerve leaves the eye. Outside the eye, six small muscles move it in every direction, the tear film keeps the surface smooth and clear, and the eyelids protect and spread that film with every blink. This video is for general education only. It is not medical advice. Ask your eye doctor what's right for you.