Question

Given is the diagrammatic representation of the sectional view of cochlea. Select the correct option regarding it.

A. A - Organ of corti-responsible for maintenance of balance of the body and posture
B. B - Scala vestibuli-filled with perilymph that ends at the oval window
C. C - Scala tympani - terminates at the round window which opens to the middle ear
D. D - Basilar membrane - nerve impulses are generated against it

Answer 1

Hint: The cochlea is present in the inner ear which is associated with hearing. The inner ear also contains semicircular canals. It transforms the vibrations of the liquid present and the other structures into neural signals.

Complete answer-
The given diagram is the schematic representation of the cochlea present in the middle ear. The cochlea is associated with the hearing. Let us discuss the various parts represented and their functions.
A. represents the Organ of Corti. It is the receptor organ of hearing. It contains specialized sensory epithelium which helps in transduction of sound vibrations into neural signals.
B. represents Scala vestibuli- It is a vestibular duct which is a perilymph filled cavity in the cochlear region of the middle ear. It conducts the vibrations to the cochlea.
C. represents the Scala tympani. It is also a perilymph filled cavity in the inner ear. It extends from the round window and continues till the vestibular duct.
D. represents the basilar membrane. It is present at the base of the organ of corti. It contains main sensory receptors for hearing. It moves in response to the sound waves which leads to depolarization of the hair cells in the organ of corti.

The correct answer is option C. C - Scala tympani - terminates at the round window which opens to the middle ear.

Note:
Vestibule is the central part of the bony labyrinth which is situated behind the cochlea. The vestibular system is responsible for the balance of the body with respect to gravity. The organ of posture in the ear is a semicircular canal.