COMD 2051 : Exam 1
Document Summary
3 parts: outer ear, middle ear, inner ear. Main function: collect sound and direct it to the eardrum. ~2. 5 cm long: produces cerumen, ear wax, protects the ear from debris and keeps the ear from drying out, extends inward at an upward angle. The middle ear (me): air-filled space, tympanic membrane, ossicles: malleus, incus, stapes, eustachian tube. Tympanic membrane (tm)/eardrum: separates outer ear from middle ear, normal color=translucent pearly gray, sound waves travels through car, the vibrations of the tm cause the ossicular chain to vibrate. Ossicular chain: 3 little bones in the me, malleus, incus, stapes. Eustachian tube: connects me to nasal cavity. Ossicles: tm vibrates-> ossicles vibrate, amplify sound, send it to inner ear. Eustachian tube: equalizes pressure in the middle ear space, permits drainage of me fluids. Auditory nerve: sends signals from the cochlea and semicircular canals to the brain. Oval window: part of cochlea, movement of stapes causes movement of fluid in the cochlea.
