eyeball: Quick Facts

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Photos

Diagram of a horizontal section of the human eye showing labeled parts including the cornea, iris, lens, retina, sclera, optic nerve, and blood vessels, with internal structures and muscles visible.

Close-up of a child's blue eye, showing detailed iris patterns and fine eyelashes.

Side-by-side diagrams compare a nearsighted eye, where light focuses in front of the retina, with a normal eye, where light focuses on the retina. Both eyes are labeled with cornea, lens, retina, and sclera.

Side-by-side diagram comparing a farsighted (hyperopic) eye and a normal eye, showing how light focuses behind the retina in hyperopia and directly on the retina in a normal eye, with labeled parts including lens, cornea, sclera, and retina.

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Topics

vitreous body fundus optokinetic nystagmus Schlemm’s canal Zinn’s zonule limbus sclera uvea cornea retina tear duct and glands optic nerve eyelid Visual pigment eye colour Why do humans have eyebrows?saccade How many eyes does a spider have?

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