biology

Statement about the MECHANISM OF HEARING
There are three main components of the human ear:
The outer ear, the middle ear, and the inner ear,
The outer ear includes the visible part of the ear(PINNA), the auditory canal and the ear drum. The pinna serves to funnel sound waves(changes in ear pressure) and the waves then travel through the auditory canal. The ear drum(TYMPANIC MEMBRANE), Is made of an airtight flap of skin. Sound travel in waves and when these waves arrive at the ear drum they cause it to vibrate, following the wave form of the sound. The ear drum simplifies incoming air pressure waves to a single change with a certain amplitude. This allow for the differentiation of sound.
 
This simplification of air pressure can be represented through fourier transformation(Decomposing a complex wave into a single composite). The middle ear consists of a small air filled chamber that is located behind the ear drum within this chamber there are three smallest bones in the body known collectively as the OSSICLES which include the malleus incus and stapes. They aid in the transmission and amplification of the vibrations from the ear drum to the inner ear. Also located in the middle ear are the stapeding and tensor tympani muscles which protect our hearing through an acoustic reflex(steffening the system). There is also the round window which gets rid of excess noise and the oval wimdow which is found at the base of the stapes. The oval window is responsible for taking vibrations and communicating them to the inner ear by sending waves through the chochlear fluid.
 
The inner ear contains the chochlea which is a spiral shaped, fluid filled tube that is considered the organ of auditory transduction. It is divided lengthwise by the basilor membrane a structure that vibrate when waves from the middle ear propagate through the chochlear fluid membrane system. The basilor membrane is tonotopic so that each frequency has a characteristic frequencies are high at the basal entrance to the chochlea and low at the apex, basilor membrane motion causes the movement of the hair cells, specialized auditory receptors located within the basila membrane. The space time pattern of vibrations in the basilor membrane is converted to a spatial temporal pattern of firings on the auditory nerve, which transmits information about the sound brain stem.
 
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