The part of the human ear that conducts air between the middle ear and the back of the throat to equalize pressure on either side of the eardrum is called the eustachian tube.
Eustachian tube connects the middle ear with the nasal cavity. It allows pressure release of the middle ear, preventing trauma that caused by high pressure differences called barotrauma. Eustachian tube is normally closed to prevent bacteria inside nasal cavity enter the ear. It only opened in a certain condition like swallowing.
