Ears

thrre major areas

External ear, middle ear, internal ear

The auricle(pinna)

Outer part that captures sound

Funnels it into the auditory canal

External acoustic meatus(auditory canal)

carries the sound to the ear drum

Tympanic membrane(ear drum)

Boundary between the external and middle ear

Connective tissue membrane that vibrates in response to sound

Transfers sound energy to bones of middle ear

3 bones of the middle ear in order of outer to inner

Malleus- make contact with the ear drum

Incus-middle one

Stapes-smallest

Internal ear

contains sensory organs for hearing and equilibrium

Mechanoreceptors

Receptors for hearing and balance

Cochlea

Transmits info through the cochlear nerve

Combines together vestibulocochlear nerve (cranial nerve VIII)

3 chambered

Scala vestibuli

Upper chamber

scala media (cochlear duct)

middle chamber

Scala tymapni

bottom chamber

vestible

Transmits info through the vestibular nerve

semicircular canals

three fluid-filled canals in the inner ear responsible for our sense of balance

ampulla

base of the semicircular canals that hold cristae ampullares

cristae ampullares

for balance of the head

Uttricle

upper sac and is continues with the semicircular canals

Saccule

lower sac and is continuous with cochlear duct

pharyngotympanic(auditory tube)

Balances the pressure between the middle ear and atmospheric pressure