When the tympanic membrane vibrates, it causes the ossicles to vibrate and hit a membrane called the ________.

Tympanic Membrane

Also known as the eardrum, it's a thin membrane that separates the outer ear from the middle ear and vibrates in response to sound waves.

Ossicles

Small bones; specifically, one of the bones of the tympanic cavity or middle ear.

Membrane

A selective barrier; it allows some things to pass through but stops others. Such membranes can be biological or synthetic.