Collectively called the auditory ossicles. what do you call this membrane?

Tympanic membrane.

Explanation:

Sound is a type of mechanical energy, the result of the transmission of energy from vibrating air particles from a sound source to more distant parts. Sound frequency is a concept that characterizes the pitch of a sound, defining it as low, medium or high. The tympanic membrane separates the outer ear from the middle ear. The main function of the outer ear is the protection of the eardrum membrane maintain a certain temperature and humidity balance necessary to preserve the elasticity of the membrane. Contributing to these functions are ceruminous cerumen-producing glands, hair, and epithelial migration from internal to external. The ossicles (hammer, anvil, and stirrup) form a bridge conducting the eardrum vibrations to the inner ear. At waves arrive in the form of amplified mechanical energy. The middle ear consists of the eardrum and three ossicles: hammer, anvil, and stirrup. It transfers through the ossicles the vibratory movement of the eardrum to the oval window of the cochlea.

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