Final answer:
The epiglottis is a piece of elastic cartilage that covers the opening of the trachea during swallowing, preventing food and beverages from entering the trachea. It swings downward to close the glottis and ensures that food passes to the esophagus, not the larynx.
Step-by-step explanation:
The epiglottis is a piece of elastic cartilage that covers the opening of the trachea during swallowing to prevent food and beverages from entering the trachea. It is attached to the thyroid cartilage and swings downward to close the glottis. This process blocks access to the trachea and bronchi, ensuring that food passes from the pharynx to the esophagus instead of the larynx.