Well,
we hear with the help of our ear. The sound produced is carried
in form a wave to the ear and hits the eardrum (That small curtain
like structure that separates the inner ear from the outer ear).
The eardrum vibrates and transmits impulses to the nerves and sends
the message to the brain. The brain understands these impulses and
hears what was said.
Have
you ever wondered why our ear has such a peculiar shape?
The ear that you see is just part of the ear that is outside the body. This shape of the ear is called pinna (pronounced as pin-nah). Pinna has such a peculiar shape because it can collect all the sound waves
(it is shaped like a cup) and sends it inside. The part of the ear
inside is called the inner ear and the middle ear. It consists of
the eardrum, the bones and muscles that vibrate and transmit sound.
Why
cant a deaf man hear?
The
deaf person may have some problem in the ear, or the nerves that
transmit sounds. As a result sound does not reach the brain. So
a deaf person cannot hear. These people are then treated with surgery,
hearing aids to help them hear.
[
And finally, you may hear " lets go to the beach"
but you may not hear "go do your homework".
That
is what you call "selective deafness"!
You hear only what you want to hear!!!!]