what is it's role in the body?
It  transmits sound vibrations from the incus to the oval window
Stapes
 transmits sound vibrations from the incus to the oval window
where is the smallest bone in the human body found In the middle ear what is it's structure? It  is the third bone of the three ossicles in the middle ear. The stapes is a stirrup-shaped bone.
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Stapes [SEP] Function
Situated between the incus and the inner ear, the stapes transmits sound vibrations from the incus to the oval window, a membrane-covered opening to the inner ear. The stapes is also stabilized by the stapedius muscle, which is innervated by the facial nerve.