American Board of Ophthalmology (ABO) Practice Exam

The primary role of the cornea is to refract light and protect the inner eye. The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Its curved shape is crucial in bending (refracting) light rays that enter the eye, allowing them to focus on the retina, which is essential for clear vision. This refractive power is one of the key factors determining the eye's overall optical system.

Additionally, the cornea serves as a protective barrier against dirt, germs, and other particles. Its surface is covered by a layer of cells that helps to keep the eye moist and provide defense against injury and infection. This dual function of refracting light for vision and providing a protective function is central to understanding the importance of the cornea in ocular health and function.

Other options describe functions that are not primarily associated with the cornea. For example, regulating intraocular pressure is largely the responsibility of the eye's drainage system and the ciliary body. The production of aqueous humor is also not a function of the cornea but is performed by the ciliary body. Moreover, color perception is primarily facilitated by the retina, particularly the photoreceptors contained within it, rather than by the cor