Eye Terms

protect the anterior portion of the eye; contain multiple glands: sebaceous, sweat, accessory lacrimal glands

vital to eye health; formed by lacrimal gland and accessory lacrimal glands and secreted as response to reflex or emotional stimuli

Thin transparent mucous membrane containing fine blood vessels provides a barrier to the external environment and nourish the eye

secrete lubricating mucus

area where the conjunctiva meets the cornea on outermost edge of iris

outer covering of the eyeball, aka "whites of the eye" dense, fibrous structure makes up posterior 5/6 of eye. maintains shape of eyeball and protects intraocular contents from trauma; slightly bluish in young people yellowish in elderly

colored circular part of the eye which hangs in front of the lens and controls the size of the pupil

the opening at the center of the iris. dilates and constricts in response to light through the dilator and sphincter papillae muscles. about 20% have unequal pupils but respond equally to light

transparent, avascular, domelike structure, forms the anterior portion of the eyeball. it is the main refracting surface of the eye. Epithelial cells are completely replaced every 7 days

the space between the cornea and the iris; filled with clear aqueous humor

produced in the posterior chamber by the ciliary body and drains into the anterior chamber through the trabecular meshwork, then through the canal of schlem, then into the vascular system; continually replenished; nourished the cornea

consists of the iris,the ciliary body and the choroid

middle covering of the eyeball containing veins and arteries which nourish the retina

composed of 10 microscopic layers and has the consistency of wet tissue paper. it is the innermost covering of the eyeball containing nerve fibers connecting with the brain through the optic nerve. Landmarks of retina can be viewed through the pupil and include the optic disc the retinal vessels and the macula.

point of entry of the optic nerve into the retina

emerge from the center of the optic disc

Area of the retina responsible for central vision; two important layers of the retinal pigment epithelium which absorbs light and the sensory retina which contains rods (night or low light vision)  and cones (bright light, color vision, and fine details)

colorless and almost completely transparent behind pupil and iris. enables focusing of near vision and refocusing of distance vision

the ability to focus and refocus

Largest chambers of the eye contains the vitreous humor

clear gelatinous substance, composed mostly of water and hyaloids membrane.