Write a short note on human ear.

Human ear can be easily understood if we divide it into different parts-
Outer ear- outer ear comprises of pinna which directs sound wave into the ear canal. Ear canal is a 2.5 cm long tube like structure where sound is intensified by multiple reflections. A thin stretched membrane is present at the end of ear canal which is known as ear drum.
Middle ear- the outermost part of middle ear is the ear drum which vibrates by the received sound. Three interconnected bones namely hammer, anvil and stirrup are connected to ear drum which further increase the amplitude of vibrations up to 30 times.
Inner ear- Cochlea is the innermost part of an ear. It is a coiled tube like structure which is filled with a dense liquid. The vibrations from stirrup sets vibrations in the dense fluid in cochlea. A large number of hair like structures known as auditory nerves are floating in the dense liquid. These auditory nerves sends signal to brain according the frequency of vibration and brain finally interprets the sound