Glossary Terms for The Eye

Question 1

accommodation

Answer 1

Adjustment of the lens’s curvature to allow for vision at various distances

Question 2

aqueous humor

Answer 2

Fluid that fills the eye anterior to the lens

Question 3

choroid

Answer 3

The dark, vascular, middle layer of the eye (roots: chori/o, choroid/o); part of the uvea (see below)

Question 4

ciliary body

Answer 4

The muscular portion of the uvea that surrounds the lens and adjusts its shape for near and far vision (root: cycl/o)

Question 5

cone

Answer 5

A specialized cell in the retina that responds to light; cones have high visual acuity, function in bright light, and respond to colors

Question 6

conjunctiva

Answer 6

The mucous membrane that lines the eyelids and covers the eyeball’s anterior surface

Question 7

convergence

Answer 7

Coordinated movement of the eyes toward fixation on the same point

Question 8

cornea

Answer 8

The clear, anterior portion of the sclera (root: corne/o, kerat/o)

Question 9

fovea

Answer 9

The tiny depression in the retina that is the point of sharpest vision; fovea centralis, central fovea

Question 10

iris

Answer 10

The muscular colored ring between the lens and the cornea; regulates the amount of light that enters the eye by altering the size of the pupil at its center (roots: ir, irid/o, irit/o) plural: irides

Question 11

lacrimal gland

Answer 11

A gland above the eye that produces tears (roots: lacrim/o, dacry/o)

Question 12

lens

Answer 12

The transparent, biconvex structure in the anterior portion of the eye that refracts light and functions in accommodation (roots: lent/i, phak/o)

Question 13

macula

Answer 13

A small spot or colored area; used alone to mean the yellowish spot in the retina that contains the fovea

Question 14

optic disk

Answer 14

The point where the optic nerve joins the retina; at this point there are no rods or cones; also called the blind spot or optic papilla

Question 15

orbit

Answer 15

The bony cavity that contains the eyeball

Question 16

palpebra

Answer 16

An eyelid; a protective fold (upper or lower) that closes over the anterior surface of the eye (root: palpebr/o, blephar/o; adjective: palpebral; plural: palpebrae)

Question 17

pupil

Answer 17

The opening at the center of the iris (root: pupill/o)

Question 18

refraction

Answer 18

The bending of light rays as they pass through the eye to focus on a specific point on the retina; also the determination and correction of ocular refractive errors

Question 19

retina

Answer 19

The innermost, light-sensitive layer of the eye; contains the rods and cones, the specialized receptor cells for vision (root: retin/o)

Question 20

rod

Answer 20

A specialized cell in the retina of the eye that responds to light; rods have low visual acuity, function in dim light, and do not discriminate color

Question 21

sclera

Answer 21

The tough, white, fibrous outermost layer of the eye; the white of the eye (root: scler/o)

Question 22

uvea

Answer 22

The middle, vascular layer of the eye (root: uve/o); consists of the choroid, ciliary body, and iris

Question 23

visual acuity

Answer 23

Sharpness of vision

Question 24

vitreous body

Answer 24

The transparent jelly-like mass that fills the main cavity of the eyeball; also called vitreous humor