Hearing and Equilibrium (BIO 181-201)

Question 1

auricle (external ear)

Answer 1

captures sound and goes to external auditory meatius

Question 2

external auditory meatus (external ear)

Answer 2

lined with fine hairs for protection

ceruimnous cerumen produces ear wax

Question 3

tympanic membrane (external ear)

Answer 3

double layered 
thin
fragile membrane
translucent
external and middle ear boundary

Question 4

middle ear

Answer 4

filled with air

Question 5

2 openings in middle ear

Answer 5

round and oval windows

covered with fine membrane

Question 6

middle ear air passages

Answer 6

equalizes pressure (mastoid air cells)

Question 7

middle ear auditory ossicles

Answer 7

three smallest bones in body

all have muscles and ligaments

Question 8

malleus

Answer 8

looks like club

handle connects to tympanic membrane

Question 9

incus

Answer 9

synovial joint between head of malleus and incus

Question 10

stabes

Answer 10

synovial joint between incus and stabes

footplate in oval window

Question 11

inner ear

Answer 11

• in temporal bone

- 2 systems of fluid filled bony and membranous tubes

Question 12

bony labyrinth

Answer 12

exoskeleton

cochlea for hearing

Question 13

membranous labyrinth

Answer 13

inside of bony labyrinth
series of tunnels and chambers
no air

Question 14

endolymph

Answer 14

in cochlear duct

high in potassium, low in sodium

Question 15

perilymph

Answer 15

• like CSF

- fills space between bony and membranous labyrinth

Question 16

scala vestibuli

Answer 16

area between bony labyrinth and vestibular membrane

Question 17

scala tympani

Answer 17

between bony labyrinth and basilar membrane (perilymph)

Question 18

scala media

Answer 18

between basilar membrane and vestibular membrane (endolymph)

Question 19

Organ of corti

Answer 19

in cochlear ducy

has hair and supporting cells

Question 20

hair cells

Answer 20

• hairbrush bristles
• 4 rows
• in entire spiral
• no axons
• cell body, microvilli (dendrites)
• base of hair cells rest in nerve endings of the cochlear nerve