A.Eardrum—thin piece of skin separating the outer and middle ear that vibrates and amplifies sound waves before entering the middle ear
B.Cochlea—spiral-shaped tube of the inner ear that contains nerve endings that are needed for hearing
C.Middle ear—central part of the ear that consists of the eardrum and a cavity containing three small bones
D.Eustachian tube—tube that connects the middle ear to the pharynx and equalizes air pressure on either side of the eardrum
