From the pharynx, air travels anteriorly into the larynx, while food and saliva travel inferiorly into the esophagus. A flap containing muscle and cartilage, called the epiglottis, prevents food from entering the larynx when swallowing. The larynx contains the Adams apple (voice box).
Choking occurs when something blocks the airway. The larynx can be easily blocked with food if a person fails to separate breathing from swallowing. Laughing or talking with food near the back of your mouth or within your pharynx is dangerous. To avoid this, eat at a regular pace. When in a hurry, people tend to be a little more careless. Avoid talking with your mouth full of food. Our tongue can stash only so much food within our cheeks. When talking or laughing, any food that isn't secured within the mouth could be sucked back through the pharynx and into the larynx. Make sure you know the Heimlich maneuver in case you or anyone in your vicinity starts to choke. (See CPR)