Page 949 - Atlas of Histology with Functional Correlations

Located in inner ear; receives and transmits sound

Spiral canal that makes three turns around central bony pillar called modiolus
Embedded in modiolus is the spiral ganglion composed of bipolar afferent
neurons
Interiorly partitioned into vestibular duct (scala vestibuli), tympanic duct
(scala tympani), and cochlear duct (scala media)

Cochlear duct contains receptor or hair cells in the hearing organ of Corti
Sound waves vibrate tympanic membrane, which activates the bony ossicles
in the middle ear

Bony ossicles transmit vibrations to inner ear and vibrate basilar membrane
Organ of Corti is located on basilar membrane; vibrations stimulate hair cells
in the organ
Hair cells (stereocilia displacement) in the organ of Corti convert mechanical
vibrations into nerve impulses

Impulses pass along afferent nerves in spiral ganglia of inner ear to cochlear
nerve and brain

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