Question

Identify the wrong statement regarding the mechanism of hearing.
A) External ear receives and directs the sound waves to eardrum
B) Vibrations produced in ear drum are transmitted through ear ossicles and oval window to fluid-filled inner ear
C) Movement of basilar membrane bends the hair cells
D) Nerve impulses are generated and transmitted by efferent fibres to the auditory cortex of brain
E) Cerebellum integrates information from semicircular canals of the ear and auditory system.

Answer 1

Hint: Ear being one of the five sensory organs is responsible for hearing sensations. It receives hearing stimulus in the form of waves and transfers it to the brain in the form of electrical impulses.

Complete answer
Ear can be divided into three main parts that is:
External ear: It consists of three parts that is pinna, auditory canal and ear drum. This part is responsible for collecting sound waves, training and killing germs and directing the waves towards the middle ear.
Middle ear: It consists of an eustachian tube (that equalizes pressure on either side of the eardrum) and ear ossicles (that vibrates and magnifies the sound waves).
Internal ear: It consists of vestibule (that maintains static equilibrium of body), semicircular canal (that maintains dynamic equilibrium of body) and cochlea (that converts sound waves into electrical impulse).
Similar pattern is followed by a sound wave when it enters the ear to travel through the ear and reach the brain. Therefore, the auditory system works in a systematic manner with each part having some or the other role. Therefore, as per the process mentioned above, statement mentioned in option A is correct that states that the external ear receives and directs the sound waves to eardrum. Therefore, it is an incorrect option.
Statement mentioned in option B is correct as ear drums and ear ossicles amplify the sound waves and direct them towards the inner ear to form electrical impulses. Therefore, it is an incorrect option.
Basilar membrane is present in the inner ear. Its vibration converts sound waves into electrical impulse by bending the action of hair. Therefore, C is also an incorrect option.
Statement of option D is also correct when it says that the electrical impulses are transferred to the brain to receive possible reactions.
However, the statement of option E is incorrect as the semicircular canal is responsible for maintaining dynamic equilibrium of the body and not in impulse formation. Therefore, it is the correct option.

Note:
Cochlea is responsible for converting the sound waves into electrical impulses with the help of the organ of Corti. It works as an audio receptor region for the ear. However, the process by which this action is performed by cochlea is still a mystery for scientists.