Which structure prevents food from entering the trachea during swallowing?

The epiglottis is a flap-like structure located at the base of the tongue that plays a crucial role during swallowing. When a person swallows, the epiglottis folds down over the trachea, which prevents food and liquids from entering the airway and directs them instead into the esophagus. This mechanism is vital for protecting the respiratory tract from aspiration, which can lead to choking or pulmonary complications.

The uvula, while involved in the swallowing process, primarily helps to close off the nasopharynx during swallowing to prevent food from entering the nasal cavity. Vocal cords are involved in sound production and also assist in protecting the airway during swallowing by closing off the glottis, but they do not function as a barrier like the epiglottis does. The pharynx serves as a passageway for both food and air, but it does not prevent food from entering the trachea; instead, it helps guide food toward the esophagus. Therefore, the epiglottis is the structure specifically responsible for preventing food from entering the trachea during the swallowing process.