What happens when respiratory and digestive system meet?

When the respiratory and digestive systems meet, it occurs at the level of the pharynx and the epiglottis. The pharynx is a common pathway for both air and food. It is a muscular tube that connects the nasal cavity and the oral cavity to the larynx and the esophagus.

During respiration, air passes through the nasal cavity or the oral cavity and travels down the pharynx. Simultaneously, during swallowing, food enters the oral cavity and is propelled backward by the tongue towards the pharynx.

At the junction of the pharynx, there is a small flap of tissue called the epiglottis. During swallowing, the epiglottis moves to cover the opening of the larynx, preventing food from entering the respiratory tract. This ensures that food is directed into the esophagus and does not obstruct the airway. Reflexively, breathing temporarily stops momentarily during swallowing to facilitate a safe pathway for food into the digestive system.

Once swallowing is complete, the epiglottis returns to its resting position, allowing air to flow freely into the larynx and lungs.

Proper coordination between the respiratory and digestive systems is crucial to prevent aspiration, which is the accidental entry of food, liquids, or saliva into the respiratory tract. This coordination is accomplished through a complex interplay of muscles, nerves, and sensory receptors in the pharynx and surrounding structures.