The sclera, the tough protective outer shell of the eyeball, is composed of dense fibrous tissue that covers four-fifths of the eyeball and provides attachments for the muscles that move the eye.
The eyeball is a bilateral and spherical organ, which houses the structures responsible for vision. It lies in a bony cavity within the facial skeleton – known as the bony orbit.
Eye Anatomy: Parts of the Eye Outside the Eyeball The eye sits in a protective bony socket called the orbit. Six extraocular muscles in the orbit are attached to the eye. These muscles move the eye up and down, side to side, and rotate the eye. The extraocular muscles are attached to the white part of the eye called the sclera.
Your eyeball is a fluid-filled sphere about 24 millimeters across, roughly the size of a gumball. Packed inside that small space are specialized tissues, transparent gels, light-sensitive cells, and over a million nerve fibers, all working together to convert light into the images you see.
Being able to describe different parts of a human eyeball. Know which parts of the eyeball are involved in accommodation. Know what a blind spot on the retina is, and where it’s located.
The eye is cushioned within the orbit by pads of fat. In addition to the eyeball itself, the orbit contains the muscles that move the eye, blood vessels, and nerves. The orbit also contains the lacrimal gland that is located underneath the outer portion of the upper eyelid.
These remarkable features of our eye are enabled by the complex structure of the eyeball. The eyeball consists of three layers; fibrous, vascular and nervous (retina). Functionally, the most important layer is the retina, which receives the external visual stimuli.