eye functions

fovea lutea

A depression in the center of the macula lutea of the retina, containing cones only and lacking blood vessels; the area of highest visual acuity (sharpness of vision).

suspensory ligament

A fold of peritoneum extending laterally from the surface of the ovary to the pelvic wall.

optic disc

A small area of the retina containing openings through which the axons of the ganglion cells emerge as the optic (II) nerve. Also called the blind spot.

vitreous humor

A soft, jellylike substance that fills the vitreous chamber of the eyeball, lying between the lens and the retina.

lens

A transparent organ constructed of proteins (crystallins) lying posterior to the pupil and iris of the eyeball and anterior to the vitreous body.

ciliary body

One of the three parts of the vascular tunic of the eyeball, the others being the choroid and the iris; includes the ciliary muscle and the ciliary processes.

choroid

One of the vascular coats of the eyeball.

iris

The colored portion of the vascular tunic of the eyeball seen through the cornea that contains circular and radial smooth muscle; the hole in the center of the iris is the pupil.

retina

The deep coat of the posterior portion of the eyeball consisting of nervous tissue (where the process of vision begins) and a pigmented layer of epithelial cells that contact the choroid.

conjunctiva

The delicate membrane covering the eyeball and lining the eyes.

pupil

The hole in the center of the iris, the area through which light enters the posterior cavity of the eyeball.

ora serrata

The irregular margin of the retina lying internal and slightly posterior to the junction of the choroid and ciliary body.

vascular tunic

The middle layer of the eyeball, composed of the choroid, ciliary body, and iris. Also called the uvea

cornea

The nonvascular, transparent fibrous coat through which the iris of the eye can be seen.

fibrous tunic

The superficial coat of the eyeball, made up of the posterior sclera and the anterior cornea.

aqueous humor

The watery fluid, similar in composition to cerebrospinal fluid, that fills the anterior cavity of the eye.

sclera

The white coat of fibrous tissue that forms the superficial protective covering over the eyeball except in the most anterior portion; the posterior portion of the fibrous tunic.

macula lutea

The yellow spot in the center of the retina.