Exam 2-Inner Ear

Question 1

Hair cell anatomy

Answer 1

kinocilum, hair bundle, stereocilia, afferent synapse, efferent synapse

Question 2

hair cell

Answer 2

single cells with cilia on top

• mechanoreceptors (measure force-gravity)
• linked together, move together
• at base: opening and closing of ion channels)
• has baseline level: always likes to be sending info to brain

Question 3

Ear anatomy

Answer 3

Outer Ear, Middle Ear, Inner Ear

Question 4

Outer ear

Answer 4

directional info

pinnea, auditory canal

Question 5

middle ear

Answer 5

ear drum (tympanic membrane), malleus (hammer), incus (anvil), stapes (stirrup)
-tympanic membrane: magnifies sound (able to hear softer sounds)

Question 6

inner ear

Answer 6

cochlea, semicircular canals, vestibule

Question 7

(Inner ear)

cochlea

Answer 7

• sound enters through oval window
• fluid filled (why sound must be magnified first)
• exits out round window (into vestibule)
• organ of corti: where hair cells are found

Question 8

(Inner ear)

cochlea-organ of corti

Answer 8

• haircells sit on flexible basilar membrane
• cilia embedded into false ceiling (tectorial membrane-stationary)
• forced bending and stretching of cilia (opening/closing of ion channels)

Question 9

(Inner ear)

cochlea-basilar membrane

Answer 9

• pitch (increases, energy increases, frequency increases)
• volume: wave magnitude (use membrane more recruitment) (has to do with how much membrane is pulled up
• lower volume is more accurate

Question 10

(Inner ear)

cochlea-basil/apical end

Answer 10

• basil end: near oval window; compact, dense; difficult to vibrate
• apical end: near round window; less dense; easier to vibrate

Question 11

proprioception

Answer 11

the sense of the body’s position (in whole or in part) in space
(important for posture, balance, coordinated movement)

Question 12

(Inner ear)

semicircular canals

Answer 12

• phasic (respond to change-rotational/angular acceleration)
• 3 canals (3 axis of space)
• hair cells stationary while cilia in cupula (gel)
• want to move fluid in circle so it moves in same direction
• head right; fluid left (hits cupula bending haircells to the left)
• continually spin (fluid eventually stops)
• multiple inputs (visual and fluid movement)

Question 13

(Inner ear)

vestibule

Answer 13

• static position of the head (tonic)
• linear acceleration (phasic)
• primarily static, sometimes phasic info*
• haircells: embedded, cilia in autolithic membrane with crystals (move with gravity)
• head upright (sacculus giving info)
• head to side (utriculus giving info)