Jul 20, 2008

The Throat, what does it do?

The Esophagus, also known as throat, a narrow, muscular tube about 30 centimeters (12 inches) long, starts at the pharynx, passes through the larynx and diaphragm, and ends at the cardiac orifice of the stomach. The wall of the Esophagus is made up of two layers of smooth muscles, which form a continuous layer from the Esophagus to the rectum and contract slowly, over long periods of time. The inner layer of muscles is arranged circularly in a series of descending rings, while the outer layer is arranged longitudinally. At the top of the Esophagus, is a flap of tissue called the epiglottis that closes during swallowing to prevent food from entering the trachea (windpipe). The chewed food is pushed down the Esophagus to the stomach through peristaltic contraction of these muscles. It takes only seconds for food to pass through the Esophagus, and little digestion actually takes place.

No comments: