The Small and Large Intestines

         The small intestine is a coiled tube about 6 meters long. If you were to lay it straight, it would be four or five times the length of your body. It is connected to your stomach. It is lined with muscles that also have peristalsis movement.

           The first part of the intestine is called the duodenum. From its walls flow liquid substances. Bile flows into the intestines from the liver and juice from pancreas. Bile helps digest fatty foods. Pancreatic juice helps digest starches, proteins and fats.

            

            The food becomes almost liquid in the intestine. Nutrients in the food are absorbed by the body through the blood vessels along the intestinal walls.

            The walls of the small intestines are lined with villi. These look like tiny fingers. The villi separate the food nutrients ready to be absorbed by the walls from the food that is not ready yet. Through the villi, the food nutrients flow into the bloodstream which distributes them to the cells of the body. When the oxygen in the body cells joins with the food substance, energy is released. That is where you get energy for work and play.

            What is left of the food is waste and goes to the large intestine or the colon. The large intestine is bigger and shorter than the small intestine. It is about one meter long. It almost surrounds the small intestine.

            The large intestine squeezes most of the water out of the undigested food. The water passes through the walls of the large intestine and is carried by the blood to the different tissues of the body. The undigested food becomes a soft solid called feces. It contains germs and gases. This is stored in the bif intestine for 12 hours or more, then peristalsis pushes it out of the body through the rectum. This is the lowest end of the large intestine.