eye Flashcards
what is the sclera?
whites of the eye
what is the cornea?
transparent center part in front of the iris
what is the iris?
pigmented part of eye that regulates the amount of light let in
what is pupil
opening in iris
what is conjunctiva?
lining sclera and eyelid
what is conjunctivitis?
pink eye
what is the lacrimal apparatus?
produces/collects tears
what are the lacrimal canaliculi?
from lacrimal puncta to nasolacrimal duct
what is the nasolacrimal duct?
drains tears into nasal cavity, where they are eventually swallowed
what is the lens?
biconvex, transparent structure inside eyeball, changes shape to focus light rays, held in place by suspensory ligament
what is the fibrous tunic?
avascular, contains cornea for admitting and refracting light and the sclera for protecting the inner parts of the eye
what is the vascular tunic?
contains choroid that has blood vessels for nourishing retina, the iris, and the ciliary body
what is the retina?
posterior 3/4 of eye contains the pigmented layer and it absorbs excess light to prevent reflection and provides vitamin A to photoreceptors
what is the ciliary body?
the smooth muscle contacts and the suspensory ligaments relax to make the lens rounder, and the epithelial lining produces aqueous humor
what is the pigmented layer?
outer layer adjacent to choroid
what is the neutral layer?
inner layer that receives light information and photoreceptors converts it into nerve impulses that are sent via the optic nerve to the brain
what are rods?
low reduced light, black and white
what are cones?
require more light, color
what is the optic disc?
blind spot where the optic nerve exits the eye, contains no photoreceptors
what is the macula lutea?
lateral to the optic disc in the center of fovea centralis that has the sharpest vision only cones present
what is the anterior cavity of eye?
between cornea and lens and separated from posterior by the iris, filled with aqueous humor
what does the aqueous humor do?
supplies nutrients, removes waste for lens and cornea, continually produced and replaced
what is the posterior cavity?
between lens and retina, contains vitreous humor
what is vitreous humor?
helps maintain shape of eye and keep retina against choroid, not continually produced
