Cochlea a protein motor called prestin on their outer membranes; it generates additional movement that couples back to the fluid–membrane wave. This "active amplifier" is essential in the ear's ability to amplify weak sounds. The active amplifier also leads to the phenomenon of soundwave vibrations being emitted from the cochlea back into the ear canal through the middle ear (otoacoustic emissions). Otoacoustic emissions are due to a wave exiting the cochlea via the oval window, and propagating back through the middle ear to the eardrum, and out the ear canal, where it can be picked up by a microphone. Otoacoustic emissions
The Human Body (TV series) programmes on the human body. The series was produced by Richard Dale and presented by Professor Robert Winston, a fertility expert. The series used a variety of different techniques to present the topics being discussed, including endoscopes and computer graphics for internal shots, time-lapse photography to show the growth of hair and nails, magnetic resonance imaging and scanning electron microscopy. The series gained 6.3 million viewers and an audience share of 38%. The series was nominated for numerous awards, winning several, including three BAFTA awards, four RTS awards and a Peabody Award. A DVD of the series was released in