Small intestine and Large intestine as Digestive Organs

Small intestine and Large intestine as Digestive Organs Small intestine The small intestine is a winding tube about 6–8 meters long, 25 mm wide with many folds called villi or intestinal spikes. These villi are functional expands the surface of the small intestine which has an effect on food absorption process. Perform the following experiment for determine the effect of folds on the absorption process. The small intestine is divided into three parts as follows: a. duodenum (12 finger intestine), length ± 25 cm, b. jejunum (empty intestine), length ± 7 m, c. ileum (absorptive intestine), length ± 1 m. Anatomical structure and histology of the small intestine. Chymy from the stomach contains starch molecules that have been digested in the mouth and stomach, protein molecules that have been digested in the stomach, fat molecules that have not been digested and other substances.While in the small intestine, all starch molecules are digested more completely into glucose molecules. Meanwhile, protein molecules are digested into amino acid molecules, and all fat molecules are digested into glycerol and fatty acid molecules. Food digestion that occurs in the small intestine is more chemical in nature. Various types of enzymes are needed to help this chemical digestion process.The liver, pancreas and glands in the walls of the small intestine are able to produce digestive juices.This sap mixes with chyme in the small intestine. The digestive juices that play a role in the small intestine are in the form of bile, pancreatic juice and intestinal juice. a. Bile Fluid Bile fluid is greenish yellow, 86% water, and does not contain enzymes. However, it contains mucin and bile salts which play a role in food digestion. Bile fluid is composed of the following ingredients. 1) Water, useful as the main solvent. 2) Mucin, useful for moistening and smoothing the duodenum to prevent irritation of the intestinal walls. 3) Bile salts, contain sodium carbonate which makes bile alkaline. Bile salts also function to reduce the surface tension of fat and water (emulsify fat). This fluid is produced by the liver. The liver is the largest digestive gland in the body which weighs ± 2 kg. In the digestive system, liver functions as a form of bile, a storage place nutrients from the blood and absorption of iron fromdamaged blood. Apart from that, the liver also functions form blood in the fetus or in emergency situations,f ormation of fibrinogen and heparin for distribution to blood circulation and regulation of body temperature.Bile flows from the liver through the bile ducts and enter the small intestine. In this digestive process, bile plays a role in the process of fat digestion, namely before fat is digested, the fat must react with bile first. In addition, bile fluid functions neutralizes hydrochloric acid in chyme, stops pepsin activity on proteins, and stimulates movement intestinal peristalsis. b. Pancreatic Sap Pancreatic juice is produced in the pancreas organ. The pancreas acts as an exocrine gland produces pancreatic juice into the digestive tract and as an endocrine gland that produces hormones insulin. This hormone is released by cells in the form of islands called islets of Langerhans. This insulin functions to maintain blood sugar to remain normal and prevent diabetes mellitus. This pancreatic juice from the pancreas flows through the pancreatic duct enters the small intestine. In the pancreas There are three types of enzymes, namely lipase which helps in breakdown of fats, trypsin helps in the breakdown of protein, and amylase helps in the breakdown of starch. c. Intestinal Sap On the wall of the small intestine there are many glands capable of producing intestinal juice. Intestinal sap contains enzymes as follows. 1) Sucrase, serves to help speed up the process ofsucrose breaks down into glucose and fructose. 2) Maltase, serves to help speed up the processbreakdown of maltose into two glucose molecules. 3) Lactase, serves to help speed up the process breakdown of lactose into glucose and galactose. 4) Peptidase enzyme, serves to help speed things up the process of breaking down peptides into amino acids. Monosaccharides, amino acids, fatty acids, and glycerol the final products of digestion in the small intestine begin to be absorbed or absorbed through the walls of the small intestine, especially in parts jejunum and ileum. Apart from that, vitamins and minerals too absorbed. Fat-soluble vitamins, absorption together with the solvent, whereas Watersoluble vitamins are absorbed by bulge your intestines. Mineral absorption is very diverse with regard to chemical properties of each mineral and differences in the structure of the parts of the intestine. Throughout the small intestine is very efficient in absorption of Na+, but not for Cl–, HCO3 –, and ions bivalent. K+ ion absorption is limited to the jejunum. Fe++ absorption occurs in the duodenum and jejunum. The absorption process in the small intestine is carried out by the villi (intestinal throbbing). Inside these villi there are blood vessels, kil (lymph) vessels, and goblet cells. Here amino acids and Glucose is absorbed and transported by the blood to the liver via hepatic portal vein system, while fatty acids reacts first with bile salts to form fat emulsion. The fat emulsion together with glycerol is absorbed into in the villi. Furthermore, in the villi, fatty acids are released, then fatty acids bind to glycerin and form fat back. The fat that forms enters the center of the villi, namely into the kil (lymph) vessels. Through the blood vessels, the fat emulsion goes to the veins, while the bile salts enter the blood to the liver and formed again into bile. Ingredients that cannot be absorbed in the small intestine will be pushed to the large intestine colon. Large intestine The large intestine or colon is ± 1 meter long and consists of on, ascending colon, transversum colon, and descending colon. Between intestinal tenue (small intestine) and Crassum cecum (large intestine) there is (appendix). At the end of the cecum there is a small protrusion called appendix (worm tuft) which contains a mass of blood cells white which plays a role in immunity. Waste substances in the large intestine are pushed into the back with peristaltic movements. Residual substances This still contains a lot of water and mineral salts required by the body. Water and mineral salts then reabsorbed by the colon wall, i.e ascending colon. The remaining substances are in the large intestine for 1 to 4 days. At that time the process occurred assisted decomposition of waste substances Escherichia coli bacteria , which are capable of forming vitamins K and B12. Next with movement peristalsis, these waste substances are pushed little by little to the final digestive tract, namely the rectum and finally comes out by defecation through the anus. Defecation begins with the swelling of the part rectum due to a stimulus called the gastrocolic reflex. Then due to the contraction activity of the rectum and muscles Connecting sphincter causes defecation. In the large intestine all digestive processes are completed perfectly.