43. Biophysical Function of Outer, Middle and Inner Ear

yaboiemil's version from 2016-02-04 17:22

The Structure of the Ear



Question Answer
Outer EarAuricle (Lobe) and Auditory Canal
Middle EarHammer, Anvil, Stirrup, Auditory Tube, Ear Drum
Inner EarCochlea, Vestibular Apparatus


1. The Ear is able to compensate for any loss of intensity as the sound moves from the medium of air
to the liquid medium in the ear by the Hammer, Anvil and Stirrup and the Ear Drum,
2. The Ear drum is a lot larger than the oval window of the stirrup, which passes the sound on to the cochlea.
This means that any vibrations are transferred into just this small bone, causing a collection and increase of
waves and intensity as sound is passed onto the cochlea.


3. Sound is conducted like this:
Sound conducted from ear drum to 3 bones ->
Oval Window of the Stirrup will hit the top window of the cochlea ->
The Liquid in the Cochlea will make waves ->
These waves are detected by sensory cells in the cochlea, which send these signals into the brain


4. The Cochlea is divided into 3 passages:




Question Answer
Scala VestibuliPerilymph
Scala TympaniPerilymph
Ductus CochlearisEndolymph
PerliymphIonic composition of Cerebrospinal fluid
EndoplymphIonic composition of Intracellular fluid


5. Electrical Phenomena in the Ear: Resting potential from between the Perilymph and Endolymph becomes a
Cochlear microphone potential when the RECEPTOR CELLS in the ORGAN OF CORTI are MECHANICALLY
6. Bekesy Theory says that sound waves reach the inner ear and cause the basilar membrane to vibrate


Question Answer
CUPULEregulates balance and position
SEMICIRCULAR CANALSregulate rotations
UTRICLE and SACCULEdetect linear acceleration

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