lab 26: hearing and equilibrium

Temporal bone

Location of war structures

Auricle

Funnels sound wave vibrations from air into the external acoustic meatus

External auditory canal

Directs vibrations from sound waves in not the tympanic membrane

Auditory (pharyngotympanic) tube

equilibrates prosure of middle ear with external environment (outer ear)

Tympanic membrane

beginning of middle ear; first ear structure to vibrate in response to sound; transfers

vibrations to ossicles

auditory ossicles

transfers vibrations produced by soundwaves, from the tympanic membrane to the oval window

Cochlea

2 1/2 turns; contains receptors for hearing

semicircular canals

Ampulla at the base contain receptors for angular acceleration

Ampulla

Contains crista apullaris

Crista ampullaris

cupulla bends hair cells; transmits sense of angular accelaration

Vestibule

Contains macula saculi (with receptors for vertical acceleration) and macula utriculi

with receptors for horizontal acceleration)

Sácala vestíbuli

contains perilymph

Scalia tympani

contains perilymph

Cochlear duct

contains endolymph and spiral organ

Spiral organ

receptor organ for hearing; converts soundwave vibrations into neral impulses

Spiral ganglion

cluster of somas from neurons of the cochlea

Vestibular membrane

seperates scala vestibuli from cochlear duct

Tectorial membrane

"roof" of spiral organ; bends auditory hair cells

Basilar membrane

"base" of spiral organ

Auditory hair cells

receptor cells for hearing

Endolymph

Fluid that moves head rotation

Cupula

Gel like cap that bends when endolymph moves

Hair cells

Receptors that detect bending and convert it to signals

Sensory nerve fiber

Carry signals to brain

Saccule

Detects vertical acceleration

Utricle

detects horizontal acceleration