Ear

Question 1

Outer Ear

Answer 1

• receives sound waves

Question 2

What are the structures of the outer ear ?

Answer 2

• Auricle or pinna
• External auditory Meatus
• Tympanic Membrane or Eardrum

Question 3

Middle Ear

Answer 3

transmits sound waves from tympanic membrane to inner ear

Question 4

What are the structures of the middle ear ?

Answer 4

• Tympanic Cavity
• Auditory or Eustachian Tube
• Auditory Ossicles
  Oval and round windows

Question 5

What does the auditory ossicles consist of ?

Answer 5

• malleus, incus, and stapes

Question 6

Inner Ear

Answer 6

contains the sensorineural organs

Question 7

What are the structures of the inner ear bony labyrinth ?

Answer 7

• vestibule, semicircular canals, and cochlea

Question 8

What are the structures of the inner ear membranous labyrinth ?

Answer 8

• its utricle, saccule, semicircular ducts, cochlear duct, maculae, cristae ampullares, and organ of corti

Question 9

What is the auricle of the outer ear covered by ?

Answer 9

elastic cartilage

Question 10

What does the external auditory meatus contain?

Answer 10

ceruminous glands

Question 11

Tympanic Cavity

Answer 11

• air-filled space surrounded by temporal bone

Question 12

What is the tympanic cavity lined with ?

Answer 12

endoderm derived simple squamous epithelium

Question 13

Auditory or Eustachian Tube

Answer 13

• connects tympanic cavity to nasopharynx

Question 14

What is the auditory or eustachain tube lined with ?

Answer 14

• ciliated pseudostratified columnar epithelium

Question 15

Middle and Inner Ear Separated by two small thin membranes “

Answer 15

• oval and round windows

Question 16

What are the two small muscles that the middle ear consists of ?

Answer 16

• stapedius and tensor

Question 17

Bony Labyrinth

Answer 17

• space within temporal bone, contains perilymph fluid divided into vestibule, 3 semicircular canals, and cochlea

Question 18

Membranous Labyrinth

Answer 18

• suspended within bony labyrinth, filled with endolymph fluid
• divided into saccule and utricle semicircular ducts, cochlear ducts

Question 19

What is the receptor of the inner ear ?

Answer 19

• specialized receptor cells with stereocilia called hair cells

Question 20

What is the difference between stereocilia and cilia ?

Answer 20

• long microfilaments
• long microvilli
• don’t move
• actin/myosin

Question 21

What do all three receptors organs have in the inner ear ?

Answer 21

• sensorineural transduction system

Question 22

Organ of Corti

Answer 22

• has a basilar membrane

- longitudinally tuned to different frequencies

Question 23

Internal Ear Fluid Movement

Answer 23

• from vibration of the oval window causes a vibrational wave in the basilar membrane leading stimulation of the hair cells and thus a nerve impulse

Question 24

Crista ampullaris

Answer 24

• sensor of angular motion

- hair cells project into the cupula

Question 25

What stimulates the hair cells in the crista ampullaris ?

Answer 25

• movement of the endolymph displaces the cupula

Question 26

Where is the maculae located

Answer 26

• saccule and utricle

Question 27

What is the role of the maculae ?

Answer 27

• for gravity and linear acceleration

Question 28

What happens in the channels when their movement toward the Kinocilium ?

Answer 28

• opens channels

Question 29

What happens in the channels when their movement away the Kinocilium ?

Answer 29

• closes channels