when a low frequency sound enters the cochlea, the stereocilia of hair cells closer to the base of the basilar membrane
What happens to the stereocilia of hair cells when a low frequency sound enters the cochlea?
Answer: When a low frequency sound enters the cochlea, the stereocilia of hair cells closer to the base of the basilar membrane are primarily stimulated.
The cochlea is a spiral-shaped structure in the inner ear responsible for converting sound vibrations into electrical signals that can be interpreted by the brain. It is lined with sensory hair cells that have stereocilia on their surface.
The basilar membrane, which runs the length of the cochlea, is arranged in a gradient of stiffness, with the base being narrower and stiffer than the apex. This gradient allows for the perception of different frequencies of sound.
In the case of low frequency sounds, the longer wavelength causes the vibrations to mainly stimulate the hair cells located near the base of the cochlea. As the sound enters the cochlea, the waves travel along the basilar membrane, causing it to vibrate. This movement causes the stereocilia of the hair cells to bend, opening ion channels and generating electrical signals.
These electrical signals are then transmitted to the auditory nerve and further processed by the brain, allowing us to perceive and interpret the low frequency sound. Overall, the specific location of the stimulation depends on the frequency of the sound, with low frequency sounds primarily activating hair cells closer to the base of the basilar membrane.