Ear and the hearing process
The ears The structure of an ear Outer ear Middle ear Inner ear The hearing process
The ears one of the 5 sense organs detect sound provide the sense of hearing help to detect the movement of the body help to keep the balance of the body by detecting the position of the head
The structure of an ear Divided into 3 parts: outer ear middle ear inner ear
Outer ear Consists of 3 structures: ear pinna collects and directs sound waves ear canal directs sound waves to eardrum eardrum vibrates when hit by sound waves
Middle ear Consists of 4 structures: ear bones 3 ear bones amplify sound vibrations pass on vibrations to oval window
Middle ear Consists of 4 structures: ear bones transmits sound vibrations to inner ear oval window
Middle ear Consists of 4 structures: ear bones releases pressure from sound waves oval window round window
Middle ear Consists of 4 structures: ear bones equalizes pressure on both sides of eardrum oval window round window Eustachian tube
Inner ear Consists of 2 structures: semicircular canals contain sensory hair cells detect the directions of head movement
Inner ear Consists of 2 structures: semicircular canals cochlea contains sensory hair cells which detect pressure changes and produce nerve impulses
The hearing process 1 The ear pinna collects sound waves. Sound waves pass along the ear canal.
The hearing process 2 Sound wave makes the eardrum vibrate.
The hearing process 3 Ear bones move to amplify and transmit the vibrations to the oval windows.
The hearing process 4 Oval window vibrates and 5 makes the perilymph in the cochlea vibrate.
The hearing process 6 Perilymph transmits vibration to endolymph.
The hearing process 7 Sensory hair cells in endolymph are stimulated and send off nerve impulse.
The hearing process 8 Auditory nerve transmits nerve impulses to the brain.
The hearing process 9 Auditory centre interprets the nerve impulses.
The hearing process 10 Pressure built up in perilymph is released at the round window.
Summary The structure of an ear ear bones semicircular canals ear pinna ear canal eardrum oval window round window cochlea Eustachian tube
The hearing process Collection of sound waves transmission of sound waves amplification of sound waves + vibration of body liquid detection of vibration transmission of nerve impulses interpretation of nerve impulses sensation of hearing