Unit A - Parts of the Ear

Question 1

What is the pinna and what does it do? (2)

Answer 1

• the external ear
• collects sound and funnels it down the auditory canal

Question 2

What is the Auditory canal and what does it do? (1)

Answer 2

• Narrow tube that concentrates sound

Question 3

What is earwax useful for?

Answer 3

Trapping invading particles.

Question 4

What is the tympanum and what does it do? (2)

Answer 4

• Membrane (eardrum)
• Transmits sound to ossicles bones

Question 5

What is the ossicles and what does it do? (2)

Answer 5

• Three bones (malleus → incus → stapes)
• through vibrations the last ossicle strikes an inner membran called the oval window

Question 6

How is energy amplified as it moves to the inner ear? How much?

Answer 6

concentrating te energy from the larger tympanum to the smaller oval window

The force triples

Question 7

How does the ear protect itself form excessive noise? (2)

Answer 7

• Muscles restrict movement of te ossicles
• stapes pulled away from oval window

Question 8

What needs to happen in order for the tympanum to vibrate freely?

Answer 8

Air pressure on both sides of the typanum, must be equal

Question 9

What is the Eustachian tube and what does it do?

Answer 9

regulates in ear air pressure in middle ear.

Question 10

What is the Cochlea and what does it do? (3)

Answer 10

• A fluid sac with hairs
• Contains specialized hair cells (mechoreceptors) that run the length of an inner canal.
• takes Vibrations from the oval window and converts it to impulses

Question 11

How does the Cochlea relieve pressure?

Answer 11

Pushes vibrations to the round window

Question 12

What is the Organ of Corti and what does it do?

Answer 12

• Where the hair cells are embedded in the Cochlea

Question 13

What is the auditory nerve?

Answer 13

Sends audio impulses to the temperal lobe.

Question 14

Where in the Cochlea does high/low frequences stimulate?

Answer 14

High freq. - closest to the oval window
Low freq. - farthest from the oval window

Question 15

How does the cochlea register sound intensity?

Answer 15

With greater pressure.

Question 16

What can cause deafness?

Answer 16

Long exposure to loud noises.

Question 17

What is the difference between conduction deafness and nerve deafness?

Answer 17

Conduction deafness: (outer/middle ear) blockage/defomity in ear canal ruptured tympannum etc.

Nerve deafness (inner ear) cochlea damage, nerve damage, temperal lobe damage

Just need to know the how to make the distinction between the two.

Question 18

What are the Semicircular canals and what does it do? (3)

Answer 18

• Three fluid filled bone chambers (horizontal, vertical, and diagonal)
• have hair cells that detect the motion of fluids (dynamic equalibrium)
• attached to the vestibular nerve