Question

Write a short note on the organ of corti.

Answer 1

Hint: Organ of corti is the hearing organ. We can locate organs of corti on the basilar membrane that consist of hair cells. These hair cells are present in rows. Hair cells are present on the internal side of the organ. These hair cells act as auditory receptors.

Complete answer:
The organ of corti is an organ of the inner ear. This is located in the cochlea that helps in hearing. The Organs of corti have rows of hair cells, three outer hair cells and one inner row of hair cells. These hair cells have stereocilia attached to it.

Vibrations of sound waves act on these stereocilia by bending them with the help of electromechanical force. This mechanical energy is converted to electrical energy by the hair cells and this electrical energy or electrical message is sent to our brain via the auditory nerve and it helps in audition means hearing.

The major function of the organ of corti that we are studying about is to change the auditory signals and reduce the hair cell extraction of sound energy.
Hearing Loss: The organ of corti can be damaged by excessive levels of sound that leads to noise induced impairment of hearing. Specifically, the function of amplification of the outer hair of cells is most sensitive to destruction because of trauma from very loud sounds or some drugs.

Additional information:
The parts of the ear include:
- External or outer ear, it includes Pinna, External auditory canal, Tympanic membrane (eardrum).
- Middle ear (tympanic cavity) consist of Ossicles –Malleus, Incus, Stapes and Eustachian tube
- Inner ears consist of Cochlea, Vestibule and Semicircular canals.

Note: When outer hair cells are once damaged Corti results in loss of sensitivity. These cells do not regenerate, because of this reason loss of hearing is considered irreversible in mammals. Meanwhile, fishes and birds repair such damages easily.