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Intestines & Colon Good day, Hope all is well. Ready to carry on exploring the digestive tract? let's go! We have now left the stomach and are venturing into the small intestine which consists of about 3 meters of 3.81cm tubing coiled in the abdomen. This tubing leads from the stomach to the large intestine. It is in the small intestine that most of the digestion and absorption of food occurs. Food passes from the stomach by entering the duodenum, which actually is the smallest segment of the intestine. The other 2 segments of the small intestine are the jejunum and the ileum. The small intestine interior has many folds. Along the surfaces of these folds are tiny finger like projections called villi. The villis move back & forth, passing through the food as it is moving along the intestinal tract. The villi play an important part in the absorption of food from the small intestine. As food passes through the small intestine, it is taken up, or absorbed, by structures in the wall of the intestines, especially the villi, and is then secreted into the lacteals. Some of the digested food is absorbed by the numerous blood vessels that line the villi. this digested food directly enters the bloodstream. As digestion progresses in the small intestine, portions of food are moving in large quantities into the capillaries of the intestinal villi. Blood from the intestine containing these products of digestion is collected in the portal vein, which is connected to the liver. The liver removes the excess glucose from the blood and stores it as glycogen, to be used later in normalising the blood-sugar level and for supplying energy. It also attempt to detoxify harmful elements in the food ( such as pesticides ) and regulates the level of nutrition available to the body. The liver is one of the master organs in the body. It receives all end products of digestion. The bulk that remains behind is then pushed down towards the large intestine. Normally, most of the contents of the intestines have been absorbed by the time the food reaches the middle of the jejunum segment of the intestine. The tone and motility of the small intestine is increased by foods served at room temperature, fibrous foods and high carbohydrate, low fat foods. Movement is slowed by cold, dry and high-fat foods. The small intestine joins the colon in the region of the right groin. At this juncture is the ileo-cecal valve whose purpose is to control the speed of passage from the small intestine and top prevent any waste from returning to it from the large intestine. The ileo-cecal valve opens into the colon into a pouch known as the cecum, the first receptacle for waste residue. At the tip of the cecum is the appendix. Due to it's position near the waste receptacle, toxins from a high diet in meat, heavy starches, etc.. can contribute to its inflammation which may result in a condition known as appendicites. From the cecum, the large intestine ascends on the right side to the middle of the abdomen, then crosses to the left side and descends again. These 3 sections are called the ascending, transverse and descending colons. Next week we will conclude this fascinating journey into our digestive system. Wishing you all an enchanted week,