7. SENSORY EAR Flashcards
external ear
recieves and collects sound waves
frequency (pitch) and amplitude (volume)
in the middle ear sound waves go from ___ to ___
air to fluid
inner ear
fluid movement
in the inner ear soundwaves are transduced to where?
nerve impulses in the CNS
parts of the inner ear
cochlea
vestibule
fluid filled compartment
cochlea (spiral)
associated with hearing
vestibule organ & semi circular canal
associated with equilibrium, linear & gravity
acceleration and balance (rotational movement)
do sound waves travel faster through liquids?
yes
where is the inner ear embedded
in the skull temporal lobe
bony labrinth (inner ear)
cavity in bone
membranous labyrinth (inner ear)
fluid filled with endolymph (rich in potassium)
vestibular organs
saccule, utricle and semicircular ducts
what is the spiral shape of the cochlea for?
compact length
vestibular maculae
sensory areas of membrane labyrinth
utricle and saccule
important for detecting gravity and movement of endolymph
what is endolymph used for?
detecting linear acceration
support cells
for structural integrity, maintain environment for hari cells, remove damaged hair cells
otoliths
calcium carbonate concretions
add weight to gelatin matrix
what are kinocilium and stereocilia?
apical projections in vestibular maculae
semicircular duct ampullae and cristae are essential for detecting what?
rotational movement
- angular acceleration, rotational movement
sectioned cochlea
determines which wavelength is detected
spinal ganglion
contain cell bodies of bipolar neurons
what are inner hair cells of spiral organ of corti important for?
improving sensitivity
what are inner hair cells of spiral organ of corti important for?
sound transduction to electrical signal
three cell types of spiral organ of corti
- outer hair cell
- inner hair cell
- supporting cells
hair cells
mechanotransduction (sound movement to electrical signal to CNS for processing)
