Where do the air and food passages cross each other?

The air and food passages cross each other in the pharynx, which is the muscular tube that connects the mouth and nasal passages to the esophagus and trachea. During swallowing, the epiglottis, a flap of tissue, closes over the trachea to prevent food from entering the airway, directing it instead into the esophagus. This coordination is essential for ensuring that air reaches the lungs while food is directed to the stomach.