E. Middle ear: shapes way ear responds to sounds, amplifies strength of sound-induced vibrations, consists of the 3 tiny bones(each is an ossicle).
F.Malleus/hammer: large, moveable flap of skin; receives vibration from tympanic membrane, attached to the incus
G.Incus, anvil (Wolfe): Middle of 3 ossicles, connects the malleus and the stapes.
H.Stapes/stirrup: connects to inner ear (by oval window, long tube w/ fluid- conduction deafness possible).
Acoustic reflex: protects ear from intense sounds by inc pressure by 15x inc b/w eardrum and oval window or level action of malleus and incus.
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Low to moderate sound pressures = stapes push directly on oval window. High pressure = muscles attached to malleus and stapes contract (so force on oval window is decreased).