digestive system in this module we are going to learn about the anatomy and physiology of the digestive system coming to the introduction digestive system is the study of digestive tract liver and pancreas the digestive system is also called as gastrointestinal tract the food you eat takes an incredible journey through your body from the top that is from mouth to the anus The Physician who specializes in the gastrointestinal tract is called gastroenterologist organs Optimum digestive system it includes mouth pharynx esophagus stomach small intestine and large intestine it also incorporate accessory organs that is salivary glands teeth liver gallbladder pancreas and appendix mouth mouth is the first organ involved in the digestion food enters the mouth and the teeth masticate to break the food into small particles the process of breakdown of food into small particles is called mastication salivary glands there are three pairs of salivary glands surrounded the oral cavity these exocrine glands produce a fluid called saliva at the rate of about 1.5 liters per day saliva released from these glands on the east side of the mouth narrow Ducks carry the saliva into the oral cavity these substances begin the process of digestion pharynx fairings or throat is a muscular tube about 5 inches long lined with a mucous membrane it serves as a common passage for air traveling from the nose to the windpipe and foot traveling from the oral cavity to the esophagus when swallowing a flap of tissue the epiglottis covers the trachea so that food cannot enter and become lodged there esophagus the esophagus is a 9 inches muscular tube extending from the pharynx to the stomach the rhythmic contractions of muscles in the wall of the esophagus Propel food towards the stomach this process is like a squeezing a marble stomach foot passes from the esophagus into the stomach the stomach is a composed of an upper portion called the fundus a middle section known as the body and the lower portion the pyloris rings of the muscles called sphincters controls the opening into and from the stomach the cardiac sphincter relaxes and contracts to move the food from the esophagus into the stomach the pyloric sphincter allows the food to leave the stomach when it has been significantly digested folds in the mucous membrane lining the stomach is called Rook The Rook contains digestive glands that produce enzymes and hydrochloric acid to further decompose the food particles the highly acidic fluid is produced at the rate of about 2.5 liters per day small intestine the small intestine extends for 20 feet from the pyloric sphincter to the first part of the large intestine it has three parts the geodenum only a one foot in length receives foot from the stomach as well as bile from the liver and gallbladder and pancreatic juices from the pancreas enzymes and bile helps to digest the food before it passes into the second part of the small intestine the jejunum about eight feet long the jejunum connects with the third section the ilium about 11 feet long helium attaches to the first part of the large intestine millions of tiny microscopic projections called Villi line the wall of the small intestine the capillaries in the pillay absorb the digestive nutrients into the bloodstream and lymph vessels large intestine the large intestine extends from the end of the ilium to the anus it is divided into four parts colon sigmoid colon and rectum the cecum is the pouch on the right side that attaches to the ilium by the ileocecal valve the appendix hangs from the cecum the appendix has no clear function but it causes problems when inflamed and infected the colon about five feet long has three divisions the ascending colon the transverse colon the descending column the sigmoid colon shaped like s Sigma lies at the distal end of the descending colon and leads into the rectum the rectum terminates in the lower opening of the gastrointestinal tract the large intestine receives the fluid waste products of digestion and stores these ways until they can be released from the body because the large intestine absorbs most of the water within the waste material the body can expel solid faces coming to the liver gallbladder and pancreas three important additional organs of the digestive system the liver gallbladder and pancreas place a crucial roles in the proper digestion and absorption of nutrients the liver liver is located in the right upper quadrant of the abdomen manufactures thick yellowish Brown sometimes greenish fluid called bile bile contains cholesterol bile acids and several bile pigments one of these pigments bilirubin is produced from the breakdown of hemoglobin in the liver the liver combines bilirubin wild bile and then excretes both into the duodenum they leave the body in feces the liver is continuously releases bind which then travels down the hepatic duct to the cystic duct the cystic death leads to the gallbladder a pear-shaped Sac under the Lipo which stores and concentrates the bile for later use after meals in response to the presence of food in the stomach and your denim the gallbladder contracts forcing the bile out the cystic duct into the common bile duct which joins the pancreatic ducts just before the entrance to the geodenum the deodinum thus receives a mixture of bile and pancreatic juices bile has a detergent-like effect on fats in the geodenum It Breaks A Part light large fat globules so the enzymes from the pancreas can digest the fats this is called emulsification without bile most of the fat taken into the body would remain undigested the liver besides producing bile has several other vital and important functions some of these are keeping the amount of glucose in the blood at the normal level the liver removes excess glucose from the bloodstream and stores it as glucogen in the liver cells when the blood sugar level becomes dangerously low the liver can convert stored with glycogen back into the glucose via a process called glucogenolysis in addition the liver can also convert proteins and fats into glucose when the body needs Sugar by a process called gluconeogenesis manufacture of some blood proteins particularly those necessary for blood clotting destruction of old erythrocytes and release of bilirubin liver also functions the removal of poisons from the blood that is detoxification the term hepatic portal system refers to the blood vessels that bring blood to the liver from the intestines digested food passes into the portal vein directly after being absorbed into the bloodstream from the small intestine thus giving the liver first chance at using the nutrients pancreas pancreas is both an exocrine and an endocrine organ as an exocrine gland it produces pancreatic juices filled with enzymes to digest food this passes into the geodenum through the pancreatic duct as an endocrine gland the pancreas secretes insulin this hormone needed to help release sugar from the blood acts as a carrier to bring glucose into the cells of the body to be used for energy let us see the flowchart food enters the oral cavity then as a bolus then to the pharynx from there it enters esophagus stomach and theodenum where at the duodenum the liver and gallbladders releases bile and pancreas release pancreatic juice and then the food enters the jejunum Ilium and from there it enters the large intestine the cecum colon sigmoid colon rectum anise and the faces leave the body thank you