Week 1 - Accessory Organs + Intestines

Occupies most of the Right hypochondriac and epigastric regions

• Bile production • Phagocytosis of red blood cells and bacteria • Processing nutrients (carbohydrates, fats, proteins) • Storage (vitamins, glycogen) • Formation of blood components • Detoxification of alcohol, drugs and converts toxic ammonia to urea • Heat production

• Heart • Abdominal Aorta • Hepatic Artery (Blood flow also comes from GI tract to the..) • Liver • Hepatic Veins • Back to the heart

2 - Hepatic artery and GI tract

• Hepatic artery and Portal Vein supply the Liver - Hepatic Vein exits the liver

Hepatocytes within each Lobule. These cells contain large amounts of RER (Protein synthesis), SER (Lipid synthesis), Golgi complexes (sort & package proteins for transportation) and mitochondria (ATP production) • play pivotal roles in metabolism, detoxification, and protein synthesis

They remove debris, like bacteria and worn out blood cells, from the blood as it flows past

Hepatocytes

Production is increased when there is fatty chyme in GI tract

• Bile ducts merge to form the hepatic ducts (right and left) • Hepatic ducts connect to form common hepatic duct • Cystic duct from gallbladder & common hepatic duct join to form common bile duct • Common bile duct & pancreatic duct form common duct • Common duct empties into duodenum

Gallbladder

• Neutralise acid from the stomach, • Emulsification of fat to enable digestion • Absorption of lipids, remove waste (bilirubin)

Posterior to the stomach in the epigastric region

Produce enzymes that help digest food

• Duodenum • Jejunum • Ileum (longest portion)

• The walls of the small intestine make digestive juices, or enzymes, that work together with enzymes from the liver and pancreas to do this. • Absorbing almost all of the nutrients you get from foods into your bloodstream.

• Circular folds • Villi • Microvilli • Length of small intestine

Increase the surface area to maximise absorption

Force chyme to spiral through the lumen, slowing its movement and allowing more time for absorption

• Finger-like projections of the mucosa - Contain blood capillaries, and lacteals (lymphatic capillaries) for fat absorption

• Tiny projections of the plasma membrane of the cells on the surface of the villi • Required for secretion of intestinal enzymes and absorption of nutrients

• To complete the absorption of water, ions & vitamins • Production and absorption of vitamin K and some B vitamins by bacteria • Movement of contents of the colon to the rectum • Formation of faeces

• Neutralises hydrochloric acid coming from the stomach • releases gastrointestinal hormones into the bloodstream • contains digestive enzymes that facilitate the digestion and absorption of food.

• Caecum • Ascending colon • Hepatic flexure • Transverse colon • Splenic flexure • Descending colon • Rectosigmoid colon • Rectum