Ear

External ear

auricle, auditory canal

Middle ear

Chamber with ossicles

Internal ear

cochlea, vestibular system

Cup-like projection, funnels sound waves into auditory canal

auricle

Short tube, external part is cartilage, internal part within temporal bone

auditory canal

Hollow, air-filled chamber within temporal bone

middle ear

Boundary between external and middle ear, sound waves make the membrane vibrate

tympanic membrane (eardrum)

Ossicles

malleus, incus, stapes

Connected to stapes

oval window

Ensures pressure in middle ear is same as external pressure

auditory tube

Fluid-filled portion of ear with three divisions

inner ear

main inner ear cavity, contains oval window

vestibule

spiral canal in inner ear, functions in hearing

cochlea

three canals in inner ear, function for balance

semicircular canals

A series of bony canals

bony labyrinth

Continuous series of membranous sacs and ducts contained within bony labyrinth

membranous labyrinth

Bony labyrinth is filled with…

peirlymph

Membranous labyrinth is filled with…

endolymph

Sound wave transmission: step 1

auricle funnels sound waves into auditory canal

Sound wave transmission: step 2

vibration of tympanic membrane

Sound wave transmission: step 3

vibration of ossicles

Sound wave transmission: step 4

vibration of stapes in oval window transmits vibrations to perilymph of cochlea

Sound wave transmission: step 5

vibration of basilar membrane

Sound wave transmission: step 6

vibration of hair cells against tectorial membrane, triggers sensory signals to be sent to brain via CN 8

Responds to pull of gravity and velocity of head

saccule and utricle

Senses rotational movements of head

semicircular canals