Pinna of externel ear collects the sound vibretions. they enter into the ear canal.this vibretions strike the tympaneum and make it to vibret.the vibretion from the tympanic memrbrane reach the middel ear. the three bones magnify the sound vibretion.than the three bones were move from this we can hear.

The pinna located in the outer ear catches the vibrations. The vibrations pass on through ear canal to strike a  membrane called ear canal. Then the vibrations pass on through three interlocked bones (hammer, anvil, stirrup) and finally reaches cochlea through auditary nerve. The cochlea interprets the vibrations to make the sound heard by us. 
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