Ear is the organ which is not only has hearing function but also help in balance of our body .Means they are phonoreceptors as well as statoreceptors.Man has one pair of ears , one on each lateral side of head....
External ear : It is formed of two parts
A) Pinna : (also known as auricle ). It is roughly funnel shaped and has ridges and grooves .It is supported by an elastic cartilage and has a funnel shaped aperture known as concha .In man , though three auricular muscles are present but are vestigial , so pinna is mostly immovable .
Function of pinna : Collection of sound waves by concha of pinna
B)External auditory canal or maetus : It is a small , oblique and tubular canal which runs inward from concha to ear drum . It is internally lined by skin whose outer part is hairy to prevent the entry of dust particles, while its inner part is with about 4000 ceruminous(ear wax) glands whose waxy secretion called cerumen (ear wax ) is to lubricate and protect the ear drum. IT is also prevents the entry of insects and microbial infection .
Function is to concentrate the sound waves to increase their pressure .