Which structures are the bones of the middle ear that transmit sound vibrations?

The ossicles are the three small bones located in the middle ear responsible for transmitting sound vibrations from the eardrum to the inner ear. These bones—known as the malleus, incus, and stapes—play a crucial role in the hearing process. When sound waves hit the eardrum, it vibrates, and these vibrations are amplified and transferred through the ossicles. The stapes, the smallest bone in the human body, connects to the oval window of the cochlea, the beginning of the inner ear, where the vibrations are converted into electrical signals for the brain to interpret as sound.

The other structures mentioned serve different functions. The semicircular canals are part of the inner ear involved in balance and spatial orientation, not sound transmission. The Eustachian tube helps equalize pressure in the middle ear with atmospheric pressure but does not play a direct role in sound transmission. The vestibule, also part of the inner ear, is involved in balance and the perception of gravitational forces rather than in hearing. Thus, the ossicles are the definitive answer in the context of sound vibration transmission in the middle ear.