freak

20/200

legal blindness, able to see stop sign

myopia

nearsightedness

emmetrophia

20/20 vision

external ear

involved in hearing only

inner ear

contains pinna and external auditory canal

hearing & balance

filled w/ perilymph and endolymph

ciliary body

smooth muscle which attaches lens to a suspensory ligament

iris

pigmented layer that gives the eye color

cornea

transparent, central anterior position

pain main fibers

allows for light to pass through

cornea

repairs itself easily

only tissue that can be transplanted w/o rejection because it has no blood vessels

external auditory canal

narrow chamber in temporal lobe with ceruminous glands

ends at tympanic membrane

bones of tympanic cavity

mallus, incus, and stapes

transfer sound to inner ear

dynamic equilibrium

receptors found in semicircular canals

respond to angular or rotary movements

against endolymph

nerve to cerebellum

receptor region

crista ampullaris (hair)

cupula covers hair cells

dragging stimulates hair

20/80

able to read alarm clock @ 10ft

news headline are this size

eye reflexes

internal muscles are controlled by autonomic nervous system - causes accomodation

external muscles causes eye movement to follow muscles - causes convergence

astigmatism

unequal curvatures in the cornea or lens

hyperopia

farsightedness

cone sensitivity

3 types, different wavelengths

rods

found at the edge of the retina

allow dim light vision and peripheral vision

perception all in grey

conduction deafness

interference w/ sound vibrations

ruptured eardrum

causes by ear wax build up

lens

bioconvex crystal-like structure held in place by a suspensory ligament attached to the cilliary body

pin-points light to the back of the retina

eye set for distance vision

middle ear/ tympanic cavity

air-filled within temporal lobe

2 tubes associated w inner ear

auditory tube connects w/ throat

organs of corti

in cochlea

hair dances with sound

cochlear nerve is attached and transmits nerve impulses to auditory cortex

maculae

receptors in vestibule

receptors in the vestibule report on position of head

contain otolithic membranes

otolithic membranes

hairs receptor cells and otoliths

otoliths

tiny calcium carbonate crystals in the inner ear's utricle and saccule that detect linear acceleration, gravity, and head tilts

sensorineural deafness

degeneration of receptor cells in the organ of corti, cochlear nerve and neurons of the auditory cortex

result of loud music