stereocilium
Quick Summary
Stereocilia are hair-like projections found on the tips of hair cells in the inner ear, specifically within the cochlea and vestibule. These structures are crucial for converting vibrations from sound waves and head movements into electrical signals that the brain can interpret.1
Key aspects of stereocilia include:
* Arrangement: They are arranged in a staircase pattern of graded lengths, forming a "hair bundle".2
* Function in Hearing: In the cochlea, stereocilia are part of the organ of Corti and play a role in transmitting auditory information.2
* Function in Balance: In the vestibular system, stereocilia, along with a single kinocilium, help the brain understand the head's orientation and movement, which is essential for balance and stabilizing vision.13
* Mechanism: Bending of stereocilia toward the kinocilium opens ion channels, leading to depolarization, while bending away closes them, causing hyperpolarization. This change in electrical potential is transmitted to neurons.13
While stereocilia are vital for sensory functions, the kinocilium, though structurally similar, is nonmotile and plays a role in development and sensory processes.1
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human earVestibule…of the hairlike cilia—stiff nonmotile stereocilia and flexible motile kinocilia—that project from their apical ends. The nerve fibres are from the superior, or vestibular, division of the vestibulocochlear nerve. They pierce the basement membrane and, depending on the type of hair cell, either end on the basal end of the…
Read More…of the hairlike cilia—stiff nonmotile stereocilia and flexible motile kinocilia—that project from their apical ends. The nerve fibres are from the superior, or vestibular, division of the vestibulocochlear nerve. They pierce the basement membrane and, depending on the type of hair cell, either end on the basal end of the…
Read More- vestibular systemVestibular structures
…of about 100 fine nonmotile stereocilia of graded lengths and a single motile kinocilium. The single kinocilium, which is larger and longer than the stereocilia, rises from a noncuticular area of the cell membrane at one side of the cuticular plate. The longest stereocilia are those closest to the kinocilium.…
Read More…of about 100 fine nonmotile stereocilia of graded lengths and a single motile kinocilium. The single kinocilium, which is larger and longer than the stereocilia, rises from a noncuticular area of the cell membrane at one side of the cuticular plate. The longest stereocilia are those closest to the kinocilium.…
Read More - human earOrgan of Corti
…a tuft of stiffly erect stereocilia, also containing actin, of graded lengths arranged in a staircase pattern. This so-called hair bundle has rootlets anchored firmly in the cuticular plate. On the top of the inner hair cells 40 to 60 stereocilia are arranged in two or more irregularly parallel rows.…
Read More…a tuft of stiffly erect stereocilia, also containing actin, of graded lengths arranged in a staircase pattern. This so-called hair bundle has rootlets anchored firmly in the cuticular plate. On the top of the inner hair cells 40 to 60 stereocilia are arranged in two or more irregularly parallel rows.…
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- human earDetection of angular acceleration: dynamic equilibrium
, bending of the stereocilia toward the kinocilium—depolarizes the hair cells and increases the rate of discharge. Deflection away from the utricle causes hyperpolarization and decreases the rate of discharge. In superior canals these effects are reversed.
Read More, bending of the stereocilia toward the kinocilium—depolarizes the hair cells and increases the rate of discharge. Deflection away from the utricle causes hyperpolarization and decreases the rate of discharge. In superior canals these effects are reversed.
Read More - human earTransduction of mechanical vibrations
The stereocilia are graded in height, becoming longer on the side away from the modiolus. All the stereocilia are interlinked so that, when the taller ones are moved against the tectorial membrane, the shorter ones move as well. The mechanical movement of this hair bundle generates…
Read MoreThe stereocilia are graded in height, becoming longer on the side away from the modiolus. All the stereocilia are interlinked so that, when the taller ones are moved against the tectorial membrane, the shorter ones move as well. The mechanical movement of this hair bundle generates…
Read More 
sensesMechanical senses…typical internal fibre skeleton, and stereocilia, which do not have fibre skeletons. Stereocilia decrease in size with distance from the kinocilium and are functionally polarized. When the stereocilia are bent toward the kinocilium, the hair cell is excited, and the nerve fibre that contacts the cell fires action potentials. In…
Read More…typical internal fibre skeleton, and stereocilia, which do not have fibre skeletons. Stereocilia decrease in size with distance from the kinocilium and are functionally polarized. When the stereocilia are bent toward the kinocilium, the hair cell is excited, and the nerve fibre that contacts the cell fires action potentials. In…
Read More- semicircular canalFunction
The hair cells form stereocilia, protrusions that extend into the crista. The longest of the stereocilia are the kinocilia, which point in a single direction and are sensitive to movement. The kinocilia extend from the crista into the cupula, a jellylike mass that surrounds the hair cells completely, separating…
Read MoreThe hair cells form stereocilia, protrusions that extend into the crista. The longest of the stereocilia are the kinocilia, which point in a single direction and are sensitive to movement. The kinocilia extend from the crista into the cupula, a jellylike mass that surrounds the hair cells completely, separating…
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