The gastrointestinal tract (GI) involves the liver, pancreas and gallbladder. As food enters through the mouth, it passes through the GI tract. We have bacteria in the GI tract that helps to digest and break down our food into small molecules which in turn nourishes the cells of our bodies. It enters the bloodstream from the walls of the small intestine. The waste passes through the large intestine and exits our bodies as a stool. From the time we swallow food, our saliva wets the food and it slides down into the esophagus and into the stomach. Our stomach lining produces acid that digests the protein. The Pancreas then breaks down the carbohydrates and fats. These digestive juices come from small tubes or ducts. The liver produces a digestive juice known as bile. The gallbladder holds onto the bile between our meals. The bile acids dissolve fat into a watery product when the food reaches the small intestine and it combines with pancreatic juices and bile. Bacteria produces some of the enzymes needed to digest the carbohydrates. Hormones in the stomach lining causes the production of digestive juices. The brain will send messages to the nerves to rlease the chemicals. The chemicals cause the GI tract to contract ad relax which moves the food ultimately out the rectum.
