Your dog's voice box, formally the larynx, not only helps him communicate with sound but also plays an important role in protecting the respiratory tract against foreign objects.
Your dog's voice box is located in his throat, toward the front, just under his chin, in just about the same place a man would have an Adam's apple. It is made up of a series of cartilage plates; it not only produces sound but also controls the movement of air, food and liquids in your dog's throat. It opens wide when necessary to allow air to pass through the respiratory system, and closes to seal out food and liquid so the matter can travel to the stomach. Some dogs suffer from laryngeal paralysis, whereby the muscles that control the voice box stop working properly, causing difficulty breathing.