Hearing

Question 1

in the interpretion/translation/perception process of hearing, the tympanic membrane moves the [….], the [….] move the oval window, […] transforms physical motion of oval window into a […] response.

Answer 1

ossicles

neural

Question 2

how are ossicles able to transfer the impedance of sound waves in air to the impedence of sound waves in the fluid of the inner ear?

(normally when sound waves move to fluid the majority is reflected)

Answer 2

overcome by pressure 200x greater at tympanic membrane compared to inner ear by way of:

1) size of tympanic membrane to oval window is 20:1
2) lever action of the ossicles 1:3:1

thus force applied to oval window exceeds the force of waves in the air.

Question 3

degeneration of the synovial joints between ossicles can lead to […]

Answer 3

degeneration of the auditory nerve

Question 4

the cochlea of the inner ear is made up of 3 chambers:

due to movement of fluid in cochlea, you get movements of the [….], movement is transmitted to the basilar membrane.

lying between the [..and..] is the basilar membrane, that allows us to hear.

Answer 4

scala vestibuli
scala media
scala tympani

tectorial membrane

scala media and scala tympani

Question 5

sounds waves first pass through the oval window (inner ear) make two revolutions around the cochlea, before passing through the […]

Answer 5

round window

Question 6

the basilar membrane is […] at the apex of cochlea and […] at the base of cochlea. This property means that the base responds to […] frequencies and the apex responds to [….] frequencies.

Answer 6

wider at apex, stiffer at base

higher frequencies

lower frequencies

Question 7

[…] cells sit atop the basilar membrane, creating a tonotopic map (covering a full range of sounds from base to apex).

Answer 7

hair

Question 8

auditory receptors are hair cells sandwiched between the […] membrane and [….].

movement of hair cells will be sheared in relation to the […]

Answer 8

basilar membrane.
reticular lamina.

tectorial membrane.

Question 9

each hair cell consists of 100 […]. Bending of these subunits results in neuronal signalling.

Answer 9

stereocilia.

Question 10

inner hair cells are embedded in the tectorial membrane.

sound induced vibrations moving the basilar membrane up and down causes shearing of the hair cells against the [….] membrane.—>sound transduction.

Answer 10

tectorial