What is the primary function of the cornea?

The primary function of the cornea is to control and focus the entry of light into the eye. This transparent front layer of the eye plays a crucial role in refracting light rays so that they can be directed properly onto the retina, allowing for clear vision. The cornea has a significant curvature, which helps it bend light effectively, and is responsible for approximately two-thirds of the eye's total focusing power.

While the cornea does contribute to maintaining the overall shape of the eye and provides some degree of protection against foreign particles and harmful elements, its main purpose centers on light entry and focus. Additionally, nutrients to the eye are largely supplied by the aqueous humor and not the cornea itself, underscoring the specialized roles that different parts of the eye play in overall vision and ocular health.