Only the external portion of your ears are visible, but in total there are three sections--the outer ear, middle ear and inner ear--that work together to make sense of the sounds you hear. The ear is responsible not only for your ability to hear, but also for your sense of balance.
Outer Ear
The outer ear serves to funnel sounds from the outside into the ear. The skin-covered cartilage on either side of the head, called the pinna or auricle, is flexible but for most people does not move. The external auditory canal, or external auditory meatus, which is the ear passage into the skull, is lined with hairs and skin, and in an adult it measures about 1 inch long. This canal is lined with an earwax-producing membrane that serves to lubricate the ear and protect it from dirt and foreign bodies, according to KidsHealth. Also part of the outer ear is the eardrum, or tympanic membrane. This thin membrane stretches like the skin of a drum between the outer and the middle ear and helps transmit sound.
Middle Ear
The middle ear turns the sounds sent to it by the outer ear into vibrations before sending them on to the inner ear. The middle ear contains the ossicles, the three smallest bones in the human body, which serve to amplify sound waves. The malleus, or hammer, is attached to the eardrum. The incus, or anvil, attaches to the malleus, and the stapes, or stirrup, attaches to the malleus. These three bones move together like a linked chain. Sound waves reaching the eardrum cause it to vibrate and move the ossicles, sending sound into the inner ear.
Inner Ear
Inside the inner ear is the cochlea, a curled tube filled with liquid that is set into motion by the vibration of the ossicles. Lined with cells covered with tiny hairs that move upon stimulation, the cochlea converts vibration to electrical impulses that are sent to the brain via the cochlear nerve, where they are deciphered as sound.
Balance
The inner ear also acts as the body's organ of balance. Information from the fluid-filled canals of the inner ear are sent to the brain through the vestibular nerve. Along with the inner ear, the eyes and muscles allow the brain to pinpoint the body's position and maintain balance, according to the Better Health Channel.
Disorders
Disorders affecting the ears can cause problems with both hearing and balance. An accumulation of excess ear wax can lead to hearing problems and should be treated by a physician. Tinnitus, or ringing in the ears, can occur because of advancing age or damage to the nerve endings of the inner ear from exposure to loud noise. Swimmer's ear, or otitis externa, happens when water becomes trapped in the ear canal, leading to the growth of bacteria. Otitis media, or middle ear infection, is the most common cause of hearing loss in children. If left untreated, it can lead to hearing loss, according to the American Academy of Otolaryngology-Head and Neck Surgery. Vertigo or dizziness can occur because of an infection of the inner ear.
