what is the purpose of the nasal conchae
Nasal concha In humans, the turbinates divide the nasal airway into 4 groove-like air passages, and are responsible for forcing inhaled air to flow in a steady, regular pattern around the largest possible surface area of nasal mucosa, which, as a ciliated mucous membrane with shallow blood supply, cleans and warms the inhaled air in preparation for the lungs.
Middle ear The middle ear is hollow. In a high-altitude environment or on diving into water, there will be a pressure difference between the middle ear and the outside environment. This pressure will pose a risk of bursting or otherwise damaging the tympanum if it is not relieved. If middle ear pressure remains low, the ear drum may become retracted into the middle ear <cite>. One of the functions of the Eustachian tubes that connect the middle ear to the nasopharynx is to help keep middle ear pressure the same as air pressure. The Eustachian tubes are normally pinched off at the nose end, to prevent being clogged with mucus, but they may be opened by lowering and protruding the jaw; this is why yawning or chewing helps relieve the pressure felt in the ears when on board an aircraft.