More information about the throat

The Pharynx
The function of the pharynx is to allow food to pass to the oesophagus, and air to pass to the trachea. Usually when we breathe in the entrance to the oesophagus is closed, so air doesn’t enter the stomach, and when we swallow the larynx is closed by a flap of cartilage - the epiglottis, so food doesn’t enter the trachea. Occasionally, though, things go wrong, particularly if we eat quickly, and food or drink enters the larynx (goes the wrong way) making us choke or cough. This is a common occurrence in small babies, particularly if they are suffering from a mild viral infection of the upper respiratory tract causing snuffles. Their hunger makes them desperate to feed, but they can't breathe through a blocked nose: sometimes the mucous and milk combine to block the throat - it can be cleared by gently patting the back, or by breathing in and out through the baby's mouth via a handkerchief. Young children commonly choke because they combine gobbling with gabbling, which means both the trachea and the oesophagus are open at the same time. Besides needing a swift pat on the back to help the trachea to clear, they need advice about speaking with their mouth’s full.

The Larynx
The larynx lies at the top of the trachea, which is the cartilaginous tube leading to the lungs. The larynx itself is made up of cartilage and ligament, and it contains the vocal cords. The function of the larynx is to allow speech and also to act as a sphincter, not only to protect the trachea, but also to allow us to increase the pressure either in our lungs (for example when we need to cough to clear sputum) or in our abdominal cavity (for example during defecation).