BISC 230Lgx Lecture Notes - Lecture 9: Basilar Membrane, Ossicles, Afferent Nerve Fiber
9 Apr 2016
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Document Summary
Basilar membrane bends up and down when the luid goes by o. E. g. like a board loaing on a lake ater a speedboat goes by. Hair cells are between the tectorial and basilar membranes o. Hairs are bent as the basilar membrane moves up and down (shearing force - forces that slide against each other) Place code: cochlea has diferent parts tuned to diferent frequencies - basilar membrane breaks down the sound wave into its components. Cochlear broader base (skinnier basilar membrane) - picks up high frequency sounds. Cochlear slimmer apex (fater basilar membrane) - picks up low frequency sounds. Labeled lines from the basilar membrane relay frequency info to the brain. Stereocilium ips are connected to the stereocilium beside it by ip links. K+ channels open up as they bend toward the larger hair cell, causes depolarizaion and ca 2+ to allow neurotransmiter release. When the stereocilium bend back the other way, the ion channels close.
