anatomy chapter 8 - the ear

what is sound

Sound creates vibrations in the air that beat against the eardrum, which pushes a series of tiny bones that move internal fluid against a membrane that triggers tiny hair cells that stimulate neurons, which in turn send actions potentials to the brain which interprets them as sound

what is the main job of these three small bones

amplify sound

allows pressure in the middle ear to be equalized with the atmospheric pressure

auditory tube

what is the purpose of the pinna

catch sound waves and pass them along deeper into the ear

contains the organ of corti

cochlea

which part of the inner ear (in the labyrinth) is responsible for hearing

cochlea

structures composing the bony or osseous labyrinth

cochlea, semicircular canals, vestibule

what are the three major ares of the ear

external middle inner

the vibrations from the tympanic membrane are passed to the ______

fluid

this is important because from this point the sound waves go through ____ not ____

fluid, air

where does the sound go after the pinna

funneled down into the external acoustic meatus and toward your middle and inner ear

collectively called the ossicles (middle ear)

hammer, stirrup, anvil

each canal can detect a different kind of

head movement

the external and middle ear are only involved with

hearing

the inner ear is involved with

hearing and maintaining your equilibrium

how does spinning around make us sick

it creates a sensory conflict, sensory conflict causes motion sickness

What else occurs in your ears equally as important as hearing?

maintaining your equilibrium

what is the order sound travels from the tympanic membrane through the bones

malleus, incus, stapes

transmits the vibrations from the stirrup to the fluid in the inner ear

oval window

what is the name of the inner ear part that the stapes touches

oval window

structures composing the outer ear

pinna, external acoustic meatus (eAm), tympanic membrane

there are three semicircular canals all designed to run along ____ that go in different directions

planes

contain receptors for the sense of equilibrium

semicircular canal, vestibule

ear structures not involved with hearing

semicircular canals, vestibule

what are the smallest bones in our body

stapes, malleus, incus

the tympanic membrane is the boundary between what

the external and middle ear

the canals are able to read the direction of our head by :

the movement of the fluid

instead of being controlled by sound waves what is it controlled by

the movement of your head

how is the sense of hearing like the sense of sound

they both use fluids

vibrates as sound waves hit it, transmits the vibrations to the ossicles

tympanic membrane

we use the _____ _____ instead of the cochlea for balance

vestibular apparatus

which part is for balance

vestibular apparatus