structures

Eye

Organ of vision

Eyelids

Folds of skin, soft tissue, and a thin layer of muscles located above and below the eye; protect the front of the eye and keep its surface moist by distributing tear film

Meibomian glnds

Oil glands found in the upper and lower edges of the eyelids that help lubricate the eye (aka tarsal glands)

Lacrimal apparatus

Network of glands, ducts, canals, and sacs that produce and drain tears. The glands produce tears, which flow through the ducts to cover the surface of the eye. Tears drain into canals, flow into sacs and then into the nasolacrimal duct, which opens into the nasal cavity

Conjunctiva

Mucous membranes lining the eyelids and covering the anterior portion of the sclera

Sclera

Outer protective layer of the eye; the portion seen on the anterior portion of the eyeball is referred to as the white of the eye

Cornea

Transparent anterior part of the sclera, which is anterior to the aqueous humor and lies over the iris. It allows light rays to enter the eye.

Uvea

Layer of tissue beneath the sclera and cornea; contains the choroid, iris, and ciliary body

Choroid

Middle layer of the eyelids that, which is interlaced with many blood vessels that supply nutrients to the eye

Iris

Pigmented muscular structure that regulates the amount of light entering the eye by controlling the size of the pupil

Ciliary body

Connects the choroid to the iris; produces aqueous humor and helps change the shape of the lens for focusing

Pupil

Opening in the centre of the eye

Lens

Lies directly behind the pupil; its function is to focus and bend light

Retina

Innermost layer of the eyelids that, which contains the vision receptors

Macula

Small portion of the retina at the back of the eye, responsible for detailed central vision

Optic nerve

Cranial nerves that carries visual impulses from the retina to the brain

Aqueous humor

Watery liquid Lund in the anterior cavity of the eye. It provides nourishment to nearby structures and maintains shape in the anterior part of the eye

Vitreous humor

Jellylike substance found behind the lens in the posterior cavity of the eye that maintains its shape