The sclera provides structure, protection ad strength to the eye, according to the Manhattan Vision Associates. It is the white outer coating of fibrous tissue surrounding the iris.
The sclera, also called "the white of the eye," is the tough, opaque tissue that serves as the protective outer coat of the eye, the St. Luke's Cataract and Laser Institute explains. There are six small muscles attached to the sclera that control the eye's movements. The optic nerve also connects to the sclera at the back of the eye. Children typically have a thinner and more translucent sclera with a visible and bluish underlying tissue. In older people, the sclera often appears yellow.
Healthline states that the sclera forms the eyeball's supporting wall. It is continuous with the clear cornea and covered by the conjunctiva, a transparent mucus membrane that lubricates the eye. The area around the optic nerve has the thickest sclera. The sclera consists of the episclera, a loose connective tissue below the conjunctiva, the sclera proper, the dense white tissue providing the sclera its white color, and the lumina fusca, the innermost part composed of elastic fibers. The other parts of the eye are the cornea, pupil, iris, lens, vitreous body, retina and optic nerve.