Silmavalgete

Silmavalgete, also known as sclera, refers to the opaque, fibrous, and protective outer layer of the eyeball. It is the white part of the eye that is visible. The sclera is primarily composed of dense connective tissue, rich in collagen fibers, which gives it its strength and durability. Its main function is to maintain the shape of the eyeball and protect the delicate inner structures, such as the retina and lens.

The sclera covers approximately five-sixths of the surface of the eyeball, with the remaining anterior portion being the transparent cornea. It is relatively avascular, meaning it has a limited blood supply, which contributes to its white appearance. However, small blood vessels are present on its surface, which can become more prominent when the eye is irritated or inflamed, leading to what is commonly called "red eyes."

Muscles responsible for eye movement, the extraocular muscles, attach to the sclera. This attachment allows for precise and coordinated movements of the eye in various directions. The sclera also provides structural support and protection against external forces, helping to prevent injuries to the sensitive components within the eye. While its primary color is white, variations can occur due to genetic factors or certain medical conditions.