Outline the path of a sound wave through the external, middle and inner ear and identify the energy transformations that occur


The sound that is received is accumulated in the auricle and transferred down the auditory canal to the tympanic membrane. The tympanic membrane is responsible for the vibrations that have the same level of frequency as the sound received. The first of the ossicles (malleus) receives the vibration and is then passed to the remaining two ossicle bones (incus and stapes) which then intensify the vibration. The stapes are attached to the oval window, which then makes the fluid situated inside the cochlea to vibrate. Hair cells located in the organ of Corti recognises the vibration and passes a message along the auditory nerve to the brain. The hair cells detect different sounds due to the different movements of the hair cells which allows the brain to detect the variety of sound.
From the auricle to the tympanic membrane the energy used is sound energy. As the vibrations are passed from the tympanic membrane to the hair cells in the Organ of Corti this energy converts to mechanical energy. The energy is then converted to electrochemical as the vibrations are passed from the hair cells in the Organ of Corti to the brain. The picture below shows the section of the ears.


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