Amplify the energy that is transmitted by the stapes to the round window

Allow the drainage of fluids that travel up the Eustachian tube when we have colds

Is extremely good for chewing on, in moments of passion

Protect the inner ear by disarticulating when the sound is too loud

Amplify the energy that is transmitted by the stapes to the oval window

This amplifies the low intensity sounds that we could not otherwise hear

This allows us to detect very soft sounds

This prevents the build up of fluid draining from our sinuses during colds

Even in silence there is transmitter release to afferent nerve fibres

This reploarises the hair cells for new sounds

ear canal

pinna 

organ of Corti

none of the above

middle ear

From frequency selectivity of cochlear vibration along its length

Frequency selective vibration of the ossicles to different sounds

Frequency selectivity in the responses of the outer hair cells but not inner hair cells

Frequency selective vibration of the eardrum to different sounds

Frequency selectivity in the responses of the auditory nerve fibres but not prior structures

Likely in the subsonic frequency range

Likely a few milliHertz

Likely a few 100s Hertz

Likely a few Hertz

Likely up to 100 kiloHertz

result in frequency selective transfer of information to the nerve fibres

result in the net influx of K+ into the receptive zones

involve protein links to open mechanically-gated ion channels

result in the net influx of Na+ into the receptive zones

involve the activation of chemically-gated ion channels

The ossicles and the cochlea

The ossicles and the Eustachian tube

The eardrum, the ossicles, and the cochlea

The ossicles, the Eustachian tube and the semicircular canals

The ossicles, the cochlea and the semicircular canals

even in silence there is some vibration of the cochlear partition

sound increases K+ entry via stereocilia and blocks K+ exit from the hair cell base

even in silence there is influx of K+ through the stereocilia and out of the hair cell base

K+ entry via stereocilia occurs in silence and K+ exit from the hair cell base increases with sound

sound modulates K+ and blocks K+ exit from the hair cell base

Wax on the auditory nerve

A hole in the external ear and wax on the auditory nerve

Fluid in the middle ear and Wax in the external ear canal

Fluid on the auditory nerve

A hole in the external ear

Improve the perception of high frequency sounds

Improve the perception of pitch

Improve the ability to identify sound location

Reduce the perception of softer sounds

Decrease the ability to identify sound location