"The eardrum is rigid, and very sensitive. Even the slightest air-pressure fluctuations will move it back and forth. It is attached to the tensor tympani muscle, which constantly pulls it inward. This keeps the entire membrane taut so it will vibrate no matter which part of it is hit by a sound wave."
via Facebook http://ift.tt/2hjftcz Hearing is made possible through physical movement, rather than chemical reactions. Learn about hearing and see diagrams explaining the hearing process.