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When air is breathed in (inspired), it passes
through the nose and the nasopharynx or through the mouth and the
oropharynx. These are both connected to the larynx, a tube made of
cartilage. The vocal cords, responsible for setting up the
vibrations necessary for speech, are located within the larynx. The
air continues down the larynx to the trachea. The trachea then
splits into two branches, the left and right bronchi (bronchial
tubes). These bronchi branch into smaller air tubes which run within
the lungs, leading to the small air sacs of the lungs (alveoli).
Either food, liquid, or air may be taken in
through the mouth. While air goes into the larynx and the
respiratory system, food and liquid are directed into the tube
leading to the stomach, the esophagus. Because food or liquid in the
bronchial tubes or lungs could cause a blockage or lead to an
infection, the airway must be protected. The epiglottis is a leaf-like
piece of cartilage extending upwards from the larynx. The epiglottis
can close down over the larynx when someone is eating or drinking,
preventing these substances from entering the airway.
In laryngitis, the tissues below the level of the
epiglottis are swollen and inflamed. This causes swelling around the
area of the vocal cords, so that they cannot vibrate normally. A
hoarse sound to the voice is very characteristic of laryngitis.
Laryngitis is a very common problem, and often occurs during the
course of an upper respiratory tract infection (cold). |