What is the outermost layer of the eye called?

The outermost layer of the eye is known as the sclera, which is a tough, protective white outer coating. It provides structural support and protection to the inner components of the eye. The cornea, although it is at the very front of the eye and plays a crucial role in focusing light, is not the outermost layer overall; it is actually part of the eye's outer structure.

The conjunctiva is a thin membrane that covers the inner surface of the eyelids and extends over the sclera, but it does not encompass the entire eye like the sclera does. The aqueous humor, on the other hand, is the clear fluid found in the anterior chamber of the eye, providing nourishment and maintaining intraocular pressure, but it is not a layer of the eye itself. Therefore, the sclera is recognized as the outermost layer, protecting deeper structures, while options related to the conjunctiva and aqueous humor refer to additional elements of eye anatomy that do not serve as the outer layer.