The epiglottis is a small cartilage flap at the opening of the larynx. It is attached the root of the tongue and covers the glottis during the act of swallowing. It is a mucous membrane and also has the ability to taste because it has taste buds. The epiglottis is made of an elastic cartilage that has two surfaces, a lingual and a laryngeal. The lingual surface is positioned to face the oral cavity, whilst the laryngeal faces the larynx.
What is the function of the epiglottis?
The epiglottis has a number of functions in the human body. Its main function is to stop the passage of food and liquid into the trachea, which leads to the lungs. When we swallow the epiglottis directs the food into the esophagus rather than the trachea. This happens due to the hyoid bone which draws the larynx allowing the epiglottis to fold down and function as part of the pharynx. It is also the epiglottis that activates the gag reflex. When food is not caught by the epiglottis signals are sent to the brain which causes the cough reflex to expel the food.
The epiglottis is also responsible for allowing air to pass through the larynx and into the respiratory system. The epiglottis also has taste buds which allow us to taste our food as it is swallowed. The epiglottis is also one of the nine cartilaginous structures that make up the voice box. When a person is swallowing it becomes part of the anterior wall of the larynx. In some languages the epiglottis is used to make sounds particularly on the consonants.
The following animation shows how the epiglottis works: