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So let me just review the structure and function
of the ear. The external ear, particularly
the tympanic membrane and the bony ossicles,
convert sound waves, sound energy into mechanical
energy. And that's transmitted to the
oval window. And that oval window then sets out
vibrations inside the perilymph of the cochlea
duct. And in turn, that stimulates the basilar
membrane to vibrate and the hair cells are
stimulated as well by their interaction with
the tectorial membrane. And therefore, we get to perceive
sounds. There are also sensory receptors in
the crista ampullaris, and the macula utricle
and the macula saccules, components of the
vestibule and the semicircular canals, and
they have special sensory receptors too, hair
cells, having a very specialized function,
and the kinocilium. And those hair cells,
again, are stimulated by
movement of endolymph, either moving the
cupula in the case of the crista ampullaris
in the semicircular canal, or the macula in
the utricle and saccules. And those hair cells,
when stimulated, give information to the central
nervous system about the position of the head
and movement of the head. So thank you very
much for listening to this lecture. I hope
you now know something about the structures
within the ear, their histological structure,
and the functions of each of those structures
do to bring about hearing, and also help us
for our balance and position in space.