Eye Vocab

Accessory Structures

Extrinsic eye muscles, eyelids, conjunctiva, and lacrimal apparatus

Conjunctiva

Delicate membrane that secretes mucus, which lubricates the eye and keeps it moist

Lacrimal Apparatus

Consists of the lacrimal gland and a number of ducts that drain the lacrimal secretions into the nasal cavity

Lysozyme

Enzyme that destroys bacteria

Sclera

White of our eyes

Cornea

Crystal clear window through which light enters the eye

Choroid

Posterior of the eye; blood-rich nutritive tunic (blood-red in color)

Ciliary Body

Smooth muscle structures that are attached to the lens

Ciliary Zonule

Suspensory ligament between the lens and the ciliary body

Iris

Pigmented, colored part of the eye; arranged smooth muscle fibers that regulates the amount of light that enters

Pupil

Rounded opening in the middle of the iris

Retina

Innermost sensory layer of eye; holds vitamin A

Rods

Photoreceptor cells that allow us to see bright colors

Optic Nerve

Leaves the eyeball, carrying impulses to the brain

Optic Disk

Part of the retina that has very few rods causing a blindspot

Fovea Centralis

Tiny pit that containsonly cones and is the area of greatest visual activity

Visual Acuity

Sharpness of vision

Lens

A flexible, biconvex, crystal-like structure that focuses light entering the eye on the retina

Aqueous Humor

Clear, watery fluid in the anterior part of the eye; maintains pressure inside of the eye

Vitreous Humor

Gel-like substance in the posterior part of the eye; prevents it from collapsing in on itself

Night Blindness

Codition that hinders our ability to see at night; most common causes: prolonged vitamin A deficiency which deterioates the retina

Color Blindness

A person is lacking from one to all three cone types; most commonly lacking the red or green receptors; sex-linked condition carried on the biological female X chromosome, thus making it most common in biological men

Cataracts

Condition of the lens of the eye which causes vision to become hazy and disorted and eventually leading to blindness; those at high risks for cataracts are diabetics, heavy smokers, and those exposed to immense subjects

Glaucoma

Drainage of the aqueous humor is blocked which causes pressure in the retnia and the optic nerve; if diagnosed early, it can be treated with eye drops the increase aqueous fluid