Hair cells

  • The sound sensitive cells in our ear is called hair cells, Each has a tough spiky extensions called Stereocilia on its upper surface and each sends signal to auditory nerve fibers through its basal surface.
  • Hair cells are embedded in a layer supporting cells and are sandwiched between two sheaths extra cellular matrix, the tectorial membrane and basilar membrane.



  • Sound vibrations cause the basilar membrane to vibrate, and this motion pushes the Stereocilia against the tectoral membrane.
  • Stereocilia tilt, triggering an electrical response in the hair cells, the activated hair cell in turn activates the auditory nerve cells.
  • Hair cell membrane contains stretch activated ion channels; these channels are closed when Stereocilia is not tilted.
  • However, when the steroecilia tilt a linking the filament from one Stereocilium to the channel neighboring stereocilium pulls at the channel opening it. Positive charged ions flow into the cell and depolarizing the membrane

No comments:
Write comments
Recommended Posts × +