Which layer covers the outer surface of the eyeball?

Which layer covers the outer surface of the eyeball?

• A. Cornea
• B. Retina
• C. Iris
• D. Sclera

Answer: (D)

The outer surface of the eyeball is covered by the sclera, a tough, protective connective tissue that forms the fibrous coat around most of the eye. It gives the eye its shape and anchors the eye muscles. At the very front, the sclera transitions into the transparent cornea, which covers the anterior surface and allows light to enter. So the sclera is the main layer covering the outer surface, with the cornea serving as the front-facing part of that outer coat. The retina is the inner neural layer, and the iris is the colored diaphragm that controls pupil size.

The outer surface of the eyeball is covered by the sclera, a tough, protective connective tissue that forms the fibrous coat around most of the eye. It gives the eye its shape and anchors the eye muscles. At the very front, the sclera transitions into the transparent cornea, which covers the anterior surface and allows light to enter. So the sclera is the main layer covering the outer surface, with the cornea serving as the front-facing part of that outer coat. The retina is the inner neural layer, and the iris is the colored diaphragm that controls pupil size.