Yhe pharynx, or throat,is funnel-shaped tube connected to the posterior end of the mouth. The pharynx is responsible for the passing of massed chewed food from the mouth to the esophagus. The pharynx also plays an important role in the respiratory system, as air from the nasal cavity passes through the pharynx on its way to the larynx and eventually the lungs. Because the pharynx serves two different functions, its contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.