The clear tissue that covers the front of the eye?

The clear tissue that covers the front of the eye?

• A. Choroid
• B. Aqueous humor
• C. Cornea
• D. Pupil

Answer: (C)

The clear tissue that covers the front of the eye is the cornea. It forms the eye’s transparent, protective window and provides most of the eye’s refractive power, helping to begin focusing light as it enters. The cornea is avascular, getting its nutrients from tears and the fluid behind it, rather than from blood vessels. By contrast, the choroid is a vascular layer at the back of the eye that nourishes the retina; the aqueous humor is the clear fluid in the front chamber between the cornea and the iris/lens, not a tissue; and the pupil is the opening in the iris that regulates light entry, also not a tissue.

The clear tissue that covers the front of the eye is the cornea. It forms the eye’s transparent, protective window and provides most of the eye’s refractive power, helping to begin focusing light as it enters. The cornea is avascular, getting its nutrients from tears and the fluid behind it, rather than from blood vessels. By contrast, the choroid is a vascular layer at the back of the eye that nourishes the retina; the aqueous humor is the clear fluid in the front chamber between the cornea and the iris/lens, not a tissue; and the pupil is the opening in the iris that regulates light entry, also not a tissue.