Question

The main function of semicircular canals in vertebrates is
A. Perceive sound vibration
B. Perceive and transmit sound vibration
C. Direct the animal towards the sound
D. Perceive the motion of the head

Answer 1

Hint: Semicircular canals enable to continue the dynamic balance of the body .

Complete step-by-step answer:
1. Each of the two human ears have three semicircular canals that are placed at right angles to each other.
2. The crista ampullaris helps in perception of sensory sensations dye the sensory receptors present on them.
3. The semicircular canals to enable the dynamic balance of the body.
4. Due to which the main function of the semicircular canals is to maintain the motion of the head.
5. These canals consist of a fluid and are C- shaped.
6. They are a part of the bony labyrinth that are at right angles to each other.
7. The superior and the posterior canals help to perceive vertical head movements whereas lateral canal helps in perceiving angular head movements.
8. When the head changes its direction the endolymph lags behind due to inertia and this causes the cupula to bend the cilia of the hair cells.
9. The stimulation of these cells is significant for sending electrical signals to the brain.
10. When the stereocilia bend towards the kinocilium which is in the opposite direction it results in hyperpolarization and inhibition.
So, the correct answer is “Option D. Perceive the motion of the head”.

Note: Remember that perceiving sound vibration is the function of eardrum i.e it vibrates due to sound waves which is further passed to the three bones in the middle ear.