Special Senses

auditory tube

equalizes air pressure between the tympanic cavity and the outside air pressure

cochlea

contains spiral organ of Corti and three fluid-filled chambers: scala vestibuli, scala tympani, and cochlear duct

external auditory canal

sound wave travels through this tunnel to cause the eardrum to vibrate

malleus, incus, stapes

small bones of middle ear that conduct sound wave to inner ear

oval window

opening into the inner ear; stapes articulates with it

pinna

acts like a funnel to direct sound waves into the ear

round window

dissipates sound wave after it travels through the cochlea

semicircular canals

contains crista ampullaris and cupula for detection of rotational movement

spiral organ of Corti

contains hair cells for hearing

tympanic cavity

air-filled cavity that houses the auditory ossicles

tympanic membrane

vibrates in response to sound waves; aka the eardrum

vestibule

contains the saccule and utricle for detection of head position and when the body is still

vestibulocochlear nerve

conducts auditory equilibrium to the brain

sclera

white portion of the fibrous layer of eye

cornea

clear portion of the fibrous outer layer of the eye

conjuctiva

thin membrane that covers the anterior portion of the eye

lens

focuses light onto the retina

choroid

contains blood vessels to provide nourishment to the retina

ciliary body

muscle that pulls on the lens to bend light for near vision

iris

muscle that constricts or relaxes to regulate the amount of light that enters the eye

pupil

hole" that allows light to enter posterior chamber of eye

retina

contains photoreceptors

optic nerve

carry visual information to the brain

optic disc

place where axons of ganglion cells penetrate through wall of eye

aqueous humor

fluid that fills the anterior chamber of the eye

vitreous humor

gel-like substance that fills the posterior chamber of the eye

lacrimal gland

produces tears