Human Digestive Tract
The digestive system of the human body processes food to provide nutrients to the body. Over the course of 24 to 72 hours, food consumed will move through the entire 9 meter digestive tract. The digestive system includes the mouth, esophagus, stomach, small intestine and the large intestine. This process utilizes a combination of several chemicals and mechanical means to break down food and absorb nutrients, vitamins, and fats into the bloodstream which are necessary for the body to properly function.
The process of digestion begins when food enters the mouth. Here, the salivary glands excrete saliva which moistens the food and begins some initial break down of the food. The food is then masticated by the teeth and is transformed into a bolus. The bolus is then swallowed by the pharynx and moves into the passageway to the stomach, which is called the esophagus.
At this point, the digestive system begins breaking down the bolus. In the stomach, the bolus is mixed into an acid solution. Over the next two to six hours, depending on the size and type of the food, the food is partially broken down into semi liquid mass known as chyme.
Next, the food moves into the intestines where the majority of the break down and absorption occurs. The small intestine is divided into three parts: the duodenum, the jejunum, and the ileum. The duodenum is the smallest of the three parts. Here, enzymes from the pancreas provide most of the digestive process. In the