Identifying the functions of parts of the ear
which part of the ear changes sound to a signal that the brain can understand?
which part of the ear carries the signal to the brain?

The cochlea converts sound into electrical signals in the ear. The auditory nerve  transmits signals from ear to the brain.

Explanation:

The outer ear, middle ear and inner ear are the three parts of a human ear each performing different functions. Outer ear performs the function of collecting sound from the external environment. The specific shape of the outer ear aids this purpose.

The collected sound then reaches the eardrum by travelling through the ear canal. When the sound waves reach the eardrum, the eardrum starts  vibrating and these vibrations  then travel to the middle ear. The middle ear consists of three tiny bones namely malleus, incus and stapes.

The function of these bones is to amplify the vibrations. The amplified vibrations are then sent to cochlea located in the inner ear and  has  a  structure shaped like a snail. Cochlea is filled with a special fluid and has tiny hairs.

The sound vibrations initiate movement of the fluid and the hair cells also move with the fluid. It is this movement that converts sound signals to electric signals. This electrical signal is then carried to the brain by the auditory nerve.

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