The digestive system is one of the main organs of all living organisms. It is responsible for the fragmentation of food and its analysis into smaller, absorbable parts of different cells of the body to carry out vital processes such as building and providing the body with sufficient energy to carry out various activities through a number of different mechanical and chemical processes.
It begins with the food trip by mouth, which is the first digestive system parts until it ends the anus that comes out of which food waste and take this entire trip about six to eight hours, during which cuts the food nine meters convergence distance, which constitute the full length of the digestive system, which divides into the upper gastrointestinal tract and the channel lower gastrointestinal .
It consists the upper gastrointestinal tract from the mouth that contains the teeth and the first process of digestion by grinding the food and the secretion of saliva, which analyzes the carbohydrates and pharynx between the mouth and esophagus, which in turn connects the mouth and the stomach, esophagus up a muscular tube that is to pay the food to the stomach and a length in the normal adult human to Afarb quarter meters, but it noted that it varies between 10 to 50 cm.
After gastrointestinal digestion, the last part of the upper gastrointestinal tract, the food travels to the first part of the lower gastrointestinal tract, which absorbs nutrients from the food digested in the former digestive tract, stores food waste until it is put out, The small intestine extends from the stomach to the beginning of the large intestine and is about four to seven meters in length and has a diameter of between 2.5 cm to 3 cm.
The small intestine consists of three parts: the 12, which is about 25 to 30 cm long. Its function is to dismantle the starchy substances that have not yet been disassembled, and then there is the fasting intestine, which is about 2.5 meters long and the longest and longest parts of the small intestine, It is 3.5 meters long and is followed by food to the large intestine, whose primary function is to absorb the water’s residue from food. The large intestine represents five intestines, approximately 1.5 meters long, and the food excreted through the anus outside the body.
The length of the gastrointestinal tract is due to the large number of curvature and irregularities in it, especially in the intestine. The area of the intestinal intestine is about 250 to 400 square meters due to the presence of many intrusions inside it which increase the internal surface area in order to increase the area through which the food is absorbed. The entire surface area of the digestive system is estimated at the size of a full football field.