The
human eye is the organ which gives us the sense of sight,
allowing us to learn more about the surrounding world
than any of the other five senses. We use our eyes in
almost everything we do, whether reading, working, watching
TV, writing a letter, driving a car, and countless other
activities.
Sight
is the most precious of the five senses, and many people
fear blindness more than any other disability. |
The
eye allows us to see and interpret the shapes, colors,
and dimensions of objects in the world by processing
the light they reflect or give off. The eye is able to
see in dim light or bright light, but it cannot see objects
when light is absent.
The
eye changes light rays into electrical signals then sends
them to the brain, which interprets these electrical
signals as visual images. The eyeball is set in a protective
cone-shaped cavity in the skull called the orbit or socket
and measures approximately one inch in diameter. The
orbit is surrounded by layers of soft, fatty tissue which
protect the eye and enable it to turn easily. Six muscles
regulate the motion of the eye. Among the more important
parts of the human eye are the iris, cornea, lens, retina,
conjunctiva, the macula, and the optic nerve. |
