Overview of the Ear

Question 1

How does the outer ear help us hear?

Answer 1

It helps us figure out which direction sound came from

Question 2

What are the parts of the outer ear?

Answer 2

Pinna and ear canal

Question 3

How does the middle ear help us hear?

Answer 3

It sends a signal to the inner ear via movements of the ossicles due to the eardrum vibrating when sound that travels through the ear canal hits it.

Question 4

What are the parts of the middle ear?

Answer 4

eardrum, eustachian tube, and ossicles

Question 5

How does the inner ear help us hear?

Answer 5

When the ossicles move, it moves the fluid inside of the cochlea which subsequently moves different hair cells on it. The movement of the har cells sends a signal through the auditory nerve and to the brain. The brain then decides on what the sound means and how to respond.

Question 6

What parts of the inner ear are responsible for balance?

Answer 6

semicircular canals, utricle, and saccule

Question 7

What is the process called by which humans can hear sounds?

Answer 7

auditory transduction

Question 8

What is the ear considered?

Answer 8

a transducer; it changes acoustic energy into mechanical energy

Question 9

What are the two muscles in the middle ear that decrease the volume of incoming sound waves?

Answer 9

stapedius muscle and tensor tympani muscle

Question 10

Where is the Eustachian tube and what is its function?

Answer 10

It is in the middle ear; it equalizes air pressure and drains fluid from the ear.

Question 11

What happens if the Eustachian tube does not work properly?

Answer 11

Then fluid builds up in the ear and can cause conductive hearing loss.

Question 12

What part of the inner ear is considered the sensory end organ of balance?

Answer 12

semicircular canals

Question 13

In the inner ear, what helps with the neural transmission of sound?

Answer 13

endocochlear potential of 180 mV in the scala media; the difference in concentration of potassium in the scala media to the concentration of Sodium in the scala tympani and scala vestibuli

Question 14

What is the organ of Corti and where is it located?

Answer 14

an organ that contains the sensory cells of hearing; it lies on the basilar membrane.

Question 15

What is the tectorial membrane and what does it do?

Answer 15

it is the roof of the basilar membrane that moves the outer hair cells in response to vibrations from the ossicles.

Question 16

What is the helicotrema?

Answer 16

a point in the inner ear where the scala tympani and scala vestibuli connect

Question 17

What chambers of the cochlea contain perilymph? What ions are in perilymph?

Answer 17

scala tympani and scala vestibuli; has more sodium than potassium

Question 18

What chamber of the cochlea contains endolymph? What ions are in the endolymph?

Answer 18

Scala media; more potassium ions than sodium ions

Question 19

The ______ is between the basilar membrane and scala vestibuli.

Answer 19

oval window

Question 20

The _______ is between the scala tympani and middle ear.

Answer 20

round window

Question 21

What do outer hair cells do in the inner ear?

Answer 21

They act as transducers, turning fluid energy into mechanical energy

Question 22

What do inner hair cells do in the inner ear?

Answer 22

They clarify the sounds that come into the ear

Question 23

On the basilar membrane of the cochlea, _______ sounds hit the top of it, because it is less stiff.

Answer 23

low-frequency

Question 24

On the basilar membrane of the cochlea, _______ sounds hit the bottom of it, because tha are is more stiff.

Answer 24

high frequency

Question 25

Which part of the ear turns mechanical energy into electrical energy?

Answer 25

the inner ear