(a) Make a labelled diagram to show the internal structure of the mammalian ear.
(b) Describe the mechanism of hearing in mammals.
(c) State two ways of caring for the ear.
Explanation
(b) The mechanism of hearing in mammals begins with sound waves first reaching the pinna and passing along the auditory meatus to the ear drum. This causes vibration which passes along the ossicles. The ossides amplify the vibrations which are transmitted to the inner ear via the oval window. This sets the endolymph in the inner ear (cochlea) to vibrate. Impulses are then set up by the hair cells of the cochlea and transmitted via the auditory nerve to the brain for interpretation.
(c) Care for the ear:
(i) Clean ear regularly with cotton wool or swab to remove dust and wax. Also avoid puncturing the ear drum by avoiding sharp objects and loud noise.
(ii) Always see the doctor in case there is any ear trouble.