The ear, hearing and equilibrium

Question 1

What is the external outer ear responsible for?

Answer 1

Collects sound waves

Question 2

What does the middle ear contain?

Answer 2

• 3 auditory ossicles
• the oval window
• the round window

Question 3

What does the inner internal ear contain?

Answer 3

• Receptors for hearing

- Receptors for dynamic and static equilibrium

Question 4

What are the external ear structures?

Answer 4

• Auricle or pinna
• Externals auditory canal
• Tympanic membrane

Question 5

What is Auricle or pinna?

Answer 5

• Elastic cartilage covered with skin

- Directs sound waves towards the tympanic membrane (eardrum)

Question 6

Describe the Externals auditory canal?

Answer 6

• Curved tube of cartilage and bone leading into temporal bone
• Ceruminous glands produce cerumen (earwax)
• Cerumen lubricates and protects the external canal

Question 7

Describe the Tympanic membrane?

Answer 7

• Thin semi-transparent membrane that separates the external and middle ear
• Sound waves vibrate the tympanic membrane and transfer that energy to the ossicles

Question 8

What is the middle ear structure?

Answer 8

• Malleus
• Incus
• Stapes
• Auditory tube

Question 9

What is the inner ear divided into?

Answer 9

• The vestibule
• The cochlea
• The semicircular canals

Question 10

What are the two main division of the inner ear?

Answer 10

• Bony labyrinth

- Membranous labyrinth

Question 11

What are the three channels of the cochlea?

Answer 11

• Scala vestiboli
• Cochlea duct
• Scala tympani

Question 12

Name the three ossicles?

Answer 12

• Malleus
• Incus
• Stapes

Question 13

Where are high pitched sounds detected?

Answer 13

At the base of the cochlea

Question 14

Where are low pitched sounds detected?

Answer 14

At the apex of the cochlea

Question 15

The vestibule is responsible for what?

Answer 15

Static equilibrium

Question 16

The semi-circular canals are responsible for what?

Answer 16

Dynamic equilibrium

Question 17

What is the order of the auditory pathway?

Answer 17

1 - sound waves vibrate the tympanic membrane
2 - vibration of the ossicles transfers and amplifies the vibratory motion to the oval window
3 - pressure waves are created in the perilymph of the cochlea labyrinth
4 - pressure waves travel through the perilymph, pass through the vestibular membrane and into endolymph
5 - pressure waves in the endolymph cause the basilar membrane to vibrate. This moves the hair cells and creates an action potential (nerve impulse)

Question 18

Endolymph is found within the what?

Answer 18

Cochlear duct

Question 19

Nerve fibers that synapse with hair cells in the organ of Corti unite to form part of the _____ nerve

Answer 19

Vestibulocochlear

Question 20

Sound waves are translated into nerve impulses in the?

Answer 20

Cochlea

Question 21

The neural receptors for the sense of hearing are located in the?

Answer 21

Inner ear

Question 22

What does the oval window connect to?

Answer 22

Stapes

Question 23

What helps maintain proper air pressure in the middle ear?

Answer 23

Eustachian tube

Question 24

Name the correct pathway leading to the perception of sound?

Answer 24

Tympanic membrane, ossicles, perilymph, endolymph, hair cells

Question 25

Each crista in the semicircular ducts is covered by a gelatinous material called the?

Answer 25

Cupula

Question 26

High intensity (loud) sounds can cause deafness because they are most damaging to the?

Answer 26

Hair cells of the spiral organ of Corti

Question 27

Perilymph fills the?

Answer 27

Bony labyrinth

Question 28

What are the three major areas of the ear?

Answer 28

External ear, middle ear, inner ear

Question 29

What is the main focus of the pinna?

Answer 29

catch sound waves and pass them along further into the ear

Question 30

What is the role of the tympanic membrane?

Answer 30

Main job is to amplify sound waves so they are stronger when they enter the inner ear

Question 31

What is the role of the labyrinth?

Answer 31

• Turn those physical vibrations into electrical impulses that brain can identify as sounds.
• Helps maintain your equilibrium

Question 32

What is the basilar membrane?

Answer 32

• A stiff band of tissue that runs between the scala media and scala tympanic in the cochlea.
• Reads every single sound within the range of human hearing and communicates it immediately to the NS
• It is covered in 1000s of fibres from short to long. The short fibres vibrate to high frequency pressure and the long fibres resonate to lower frequency pressure