Lecture 26- Auditory 1

Question 1

What is a Hertz?

Answer 1

number of oscillations per unit time (cycles/sec)

Question 2

What is the impedence mismatch? How is this overcome?

Answer 2

the density in the air is much lower than the inner ear fluid

overcome b/c the eardrum is 20x larger than the footplate of the stapes

Question 3

What is the name of the window that the stapes is in?

Answer 3

oval window

Question 4

Which window is displaced as a result of fluid displacement of the fluid in the scala vestibuli?

Answer 4

round window

Question 5

Which hair cells provide the majority of input to the auditory nerve and have free standing hair cells?

Answer 5

inner hair cells

Question 6

Which hair cells have tips that are attached to the tectorial membrane?

Answer 6

outer hair cells

Question 7

What does displacement of the stereo cilia towards the tallest bundle produce?

Answer 7

opens ionic channels- influx of K+- depolarization

Question 8

What does displacement of the stereocilia away from the largest of the bundle cause?

Answer 8

closes ionic channels

Question 9

What is the resting membrane potential of a hair cell?

Answer 9

-50mV

Question 10

What ion rushes into the hair cell to cause depolarization?

Answer 10

K (NOT NA)