We just learned about the Cochlea.
Another part of the ear is the Hair Cells.
Inside the Cochlea are tiny microscopic hairs that move when sound hits them.
When these hairs move, the part of the body they are attached to lets out some chemicals.
Those chemicals then touch some other cells in the body which let out electricity.
That electricity sends the message to the brain that the body heard a sound.
Depending on how loud, soft, high or low the sound is, the hairs will wiggle differently,
and that will send different chemicals and different electricity to the brain to tell you what sounds you are hearing.
(from: wikipedia - hair cell)
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