, Cornea, the transparent dome at the front that performs most of the eye's refracting power.
, Iris, the colored ring of muscle that controls the size of the pupil.
, Pupil, the opening in the center of the iris that lets light pass into the eye.
, Lens, the flexible structure behind the iris that fine-tunes focus for near and far objects.
, Ciliary body, the ring of muscle that changes the shape of the lens (accommodation).
, Vitreous humor, the clear gel that fills the large posterior chamber and maintains the eye's shape.
, Retina, the light-sensitive layer at the back of the eye containing rods and cones.
, Macula & fovea, the central retinal region responsible for sharp, color vision.
, Choroid, the vascular layer between the retina and sclera that supplies nutrients.
, Sclera, the tough white outer coat that gives the eyeball its shape.
, Optic nerve, the bundle of over a million nerve fibers that carries visual signals to the brain.