The Ear: the Organ of Hearing

The ear is the organ of hearing. The pinna of the outer ear collects sound waves and channels them along the external auditory meatus to the ear drum. The eardrum vibrates and mechanical waves are transmitted by the ossicles, three small bones of the middle ear-the malleus, incus and stapes-to the cochlea of the inner ear. The cochlea, a coiled tube filled with fluid, contains the organ of Corti. Fluid waves, created within the cochlea, excite nerve cells in the organ of Corti, which send impulses along the auditory nerve to the brain. The semicircular canals, the saccule and the utricle are concerned with balance and the posture of the body.