Question

Chief function of semicircular canals of internal ear is

• A. Balancing and hearing
• B. To perceive sound vibrations of high frequency
• C. To maintain dynamic equilibrium of the body, while the body is in imbalance
• D. To transmit sound vibration to the auditory nerve

Answer 1

Answer: (C)

To maintain dynamic equilibrium of the body, while the body is in imbalance

As the sound travels through the perilymph, it moves the endolymph in the cochlear duct. Movements of the endolymph move the tectorial membrane, which is attached to the sensory hairs of hair cells in the organ of Corti. The hair cells are attached to the basilar membrane, which also moves with the sound vibrations. The semicircular canals contain three main parts: the horizontal, posterior, and superior canals. Each of these canals provides a separate sense of directional balance. The superior canal detects head rotations on the anterior-posterior axis. The posterior canal detects rotations on the saggital plane. The horizontal canal senses movement on a vertical basis, as the head rotates up-and-down on the neck.