The Larynx Quiz

See Introduction to the Larynx. Option A is correct. The larynx (the 'voice box') lies in the front of the neck at the level of the C3 to C6 vertebral bodies and connects the laryngopharynx (the lower part of the throat) with the trachea (windpipe). Its functions are airway protection, ventilation (a channel for air), coughing and phonation (the production of sound). Airway protection is arguably the most important. When food or fluid enters the airway this is called aspiration, and it can cause choking or a chest infection. During swallowing the epiglottis, a flap of elastic cartilage, folds over the laryngeal inlet (the opening into the larynx) so that food is diverted away and passes into the laryngopharynx instead, through recesses called the piriform fossae. The cough reflex is a second line of defence: it expels unwanted material from the airway rapidly. A plain memory aid: the larynx is the guard at the airway door, letting air in and keeping food out.

• Most important function: Airway protection, keeping food and fluid out of the lower airways.
• Mechanism: During swallowing the epiglottis folds over the laryngeal inlet, so food is diverted into the laryngopharynx.
• Second line: The cough reflex expels unwanted material from the airway.
• Other functions: Ventilation and phonation.