Answer:
The cochlea contains of tiny stereocilia, or tiny hair cells.
Step-by-step explanation:
By definition, cochlea is a snail-shaped portion of the inner ear, that belongs to the auditory system. Cochlea receives the vibrating sounds and it causes stereocilia (bundle of tiny hairs, visible in that shape only under the microscope) to move. Then, those vibrations are converted into nerve impulses, and further sent to brain so the received nerves can be processed.
That hearing is an extraordinary process, says the fact that we have over 15000 tiny hair cells! When sounds are too loud for too long, these bundles of stereocilia can be damaged. The damaged hair cells can't respond to sound, which causes noise-induced hearing loss. Since hair cells can’t be repaired or even replaced in humans, hearing loss is often permanent.