Question

Which option shows the correct sequence for mechanism of hearing?

• A. External ear $\to$ Reissner's membrane $\to$ Tympanic membrane $\to$ Cerebrum
• B. External ear $\to$ Fenestra rotunda $\to$ Auditory nerve cerebrum
• C. External ear $\to$ Tympanic membrane $\to$ Cochlear canal $\to$ Sensory cells of corti $\to$ Cerebrum
• D. External ear $\to$ Ear ossicles $\to$ Resissner's membrane $\to$ Cochlear canal $\to$ Cerebrum

Answer 1

Answer: (C)

External ear $\to$ Tympanic membrane $\to$ Cochlear canal $\to$ Sensory cells of corti $\to$ Cerebrum

During mechanism of hearing, it occurs in a particular sequence. When sound is produced, the sound waves are received by the external ear pinna. These waves then move in the ear and vibrate the tympanic membrane or ear drum. The tympanic membrane is attached to 3 bones namely malleus, incus and stapes. Upon vibration of the tympanic membrane, all the 3 bones also vibrate. Upon vibration of the stapes, the fluid within the inner ear cochlea is moved. This generates an impulse and vibration in the inner ear called as coclear canal. From cochlear canal, the nerve impulses travels to the cerebrum via sensory cells of corti. In the cerebrum, the sound is differentiated and the speech is understood in minute details.

Thus, the correct answer is 'External ear → Tympanic membrane → Cochlear canal → Sensory cells of corti → Cerebrum.'