Nightingale Anatomy Practice Exam

The cornea’s transparency comes from a highly organized arrangement of collagen fibers in the stroma. The collagen lamellae run in regular, parallel patterns with uniform fibril diameter and tight spacing, maintained by proteoglycans. This precise regularity minimizes light scattering as it passes through, and the cornea’s avascular nature helps keep it clear. In the other structures, the retina is a neural tissue and not transparent, the iris contains pigment and is not transparent, and the sclera is opaque with a less orderly collagen framework. The combination of exact collagen alignment and lack of blood vessels makes the cornea the transparent structure described.