Eye anatomy

Accommodation

Ability to focus for close vision (under 20 feet)

Fovea Centralis

Area of acute or discriminatory vision

Optic Disk

Area of retina that lacks photoreceptors

Ciliary zonule

Attaches the lens to the ciliary body

Astigmatism

Blurred vision, resulting from unequal curvatures of the lens or cornea.

Cataract

Clouding of the lens, resulting in loss of sight

Glaucoma

Condition of increasing pressure inside the eye, resulting from blocked drainage of aqueous humor

Canal of Schlemm

Drains the aqueous humor of the eye

Aqueous humor

Fluid in the anterior segment that provides nutrients to the lens and cornea

Refraction

Light bending

Convergence

Medial movement of the eyes during focusing on close objects.

Emmetropia

Normal vision

Ciliary body

Nutritive (vascular) layer of the eye

Sclera

The "white"of the eye

Myopia

nearsightedness

Hyperopia

Inability to focus well on close objects; farsightedness

Night blindness

Inability to see well in the dark; often due to Vitamin A deficiency

Retina

Layer containing the rods and cones

Iris

Pigmented "diaphragm" of the eye

Photopupillary reflex

Reflex constriction of pupils when they are exposed to bright light

Accommodation pupillary reflex

Reflex constriction of pupils when viewing close objects

Cornea, Aqueous Humor, Lens, Vitreous Humor

Refractory media of the eye