Stereocilia in ear. Coloured scanning electron micrograph (SEM) of stereocilia (yellow) in a healthy inner ear. The inner ear converts sound waves into nerve impulses by stimulation of the stereocilia, which project from the ends of sensory hair cells. Sound waves entering the inner ear displace the fluid that surrounds the stereocilia, causing the stereocilia to bend. This bending causes the release of neurotransmitter chemicals, which generate nerve impulses that travel to the brain along the auditory nerve. The inner ear can transmit information about the loudness and pitch of a sound. Magnification: x2185 at 6x7cm size.