What is a hair cell?

What is a hair cell?

• A. A neuron in the spiral ganglion
• B. A supporting cell in the organ of Corti
• C. A mechanoreceptor with an array of stereocilia emerging from its apical surface
• D. A receptor cell in the cochlear nucleus

Answer: (C)

Hair cells are sensory receptor cells in the cochlea that act as mechanoreceptors. Their apical surface bears a bundle of stereocilia, which deflect in response to sound- or vibration-induced movement. This mechanical deflection opens ion channels at the tips of the stereocilia, creating a receptor potential that triggers the release of neurotransmitter onto the afferent fibers of the spiral ganglion. There are two main types in the organ of Corti: inner hair cells primarily transduce sound into neural signals, while outer hair cells work as mechanical amplifiers to enhance sensitivity and frequency discrimination. They are not neurons themselves, nor merely supporting cells, and they reside in the cochlea rather than in the cochlear nucleus.

Hair cells are sensory receptor cells in the cochlea that act as mechanoreceptors. Their apical surface bears a bundle of stereocilia, which deflect in response to sound- or vibration-induced movement. This mechanical deflection opens ion channels at the tips of the stereocilia, creating a receptor potential that triggers the release of neurotransmitter onto the afferent fibers of the spiral ganglion. There are two main types in the organ of Corti: inner hair cells primarily transduce sound into neural signals, while outer hair cells work as mechanical amplifiers to enhance sensitivity and frequency discrimination. They are not neurons themselves, nor merely supporting cells, and they reside in the cochlea rather than in the cochlear nucleus.