physiology of hearing and balance

Question 1

what does the external ear do?

Answer 1

collect sound waves

Question 2

what does the middle ear do?

Answer 2

amplify sound waves

Question 3

what does the inner ear do?

Answer 3

sound transducer and maintains balance

Question 4

why is eustachian tube important?

Answer 4

ventilates middle ear and maintains equal air pressure across tympanic membrane

Question 5

where are the ossicles?

Answer 5

middle ear

Question 6

cochlea is for?

Answer 6

hearing

Question 7

vestibule is for?

Answer 7

balance

Question 8

what does the auricle do?

Answer 8

catches sound waves

Question 9

where does the auricle send the sound waves?

Answer 9

deeper into the ear through the external acoustic meatus

Question 10

what happens when sound waves reach the end of the external acoustic meatus?

Answer 10

they push the ear drum back and forth and make it vibrate. the vibrations are then passed onto the ossicles

Question 11

what do the ossicles do?

Answer 11

they amplify the sound to make it stronger as they move into the fluid filled cochlea. they transmit the sound waves from the tympanic membrane to the cochlea

Question 12

3 chambers in cochlea?

Answer 12

scala vestibuli
scala media
scala tympani

Question 13

what is the important membrane in the cochlea?

Answer 13

basilar membrane

Question 14

what happens in the basilar membrane?

Answer 14

the hairs in the membrane detect vibrations and transduce these into nerve impulses which pass to organ of corti.

Question 15

what sounds are heard in the short stiff hairs at start of membarne?

Answer 15

high frequency sounds

Question 16

what sounds are heard in the long wiggly hairs at start of membarne?

Answer 16

low frequency sounds

Question 17

what happens in the organ of corti?

Answer 17

action potentials eventually sent through cochlear nerve, auditory pathwya to cerebral cortex

Question 18

what is frequency?

Answer 18

number of waves that pass a certain point in a given time frame

Question 19

what makes a high pitched noise?

Answer 19

faster numerous waves

Question 20

what makes a low pitched noise?

Answer 20

slower and less waves

Question 21

what does loudness depend on ?

Answer 21

amplitude

Question 22

what is amplitude?

Answer 22

difference between the high and low pressure created in the air by that sound wave

Question 23

what does the vestibular apparatus control?

Answer 23

balance

Question 24

fluid in the vestibular apparatus is controlled by what?

Answer 24

head movement

Question 25

how is balance controlled?

Answer 25

when your head moves in a certain way, the fluid in the semicircular canals will move in a certain way and stimulate hair cells which send action potential to the brain