What parts of the respiratory system would need to be blocked to not allow any air into this system?

Air can be inhaled through the nose and through the mouth. These two openings of the airway are joined in the pharynx, in the back of the nose and mouth. The pharynx is part of the digestive system and the respiratory system because it transports both food and air. The larynx is the upper part of the airway. The trachea extends down from the base of the larynx and also removes fluids and foreign particles in the airway so that they do not enter the lungs.