1. Digestion II Biology 2122

2. Small Intestine – Gross Anatomy 1.Duodenum and Pyloric Valve 2.Pancreas and Gall Bladder – hepatopancreatic ampulla – Hepatopancreatic sphincter 3.Jejunum – 2.5 m (8 ft.) 4.Ileum – 3.6 m (12 ft.) – Ileocecal valve

3. Small Intestine – Histology 1.Plicae Circulares – Mucosa and submucosa folds 2.Villi – Capillaries and lacteals – Microvilli (Brush Border) – Simple Columnar Epithelium 3.Intestinal Crypts (Lieberkuhn) – Intestinal Juice – Enteroendocrine cells – Paneth cells – Peyer’s Patches and Brunners Glands 4. Intestinal Juice

4. Small Intestine – Digestion and Absorption SubstrateStructureEnzymesAction CarbohydratesBrush Borderglucoamylase, lactase, sucrase Oligosaccharides ------  monosaccharides ProteinsBrush Borderaminopeptidase, carboxypeptidase, dipeptidase Small polypeptides and peptides -----  amino acids Nucleic AcidsBrush bordernucleosidases, phosphatases Nucleic acids ---------  pentose sugars, phosphates, bases

5. Pancreas – Gross Anatomy and Histology 1.Retroperitoneal 2.Deep – greater curvature 3.Pancreatic duct – bile duct -  duodenum 4.Histology – Acini Cells – Pancreatic islets – pancreatic Juice

6. Pancreas – Digestion 1.Pancreatic Enzymes 2. Proteases – Proteins – Trypsin – Chymotrypsin – Carboxypeptidase – Large to small polypeptides Small intestine brush border enzymes 3. Pancreatic amylase 4. Pancreatic lipase 5. Pancreatic ribonuclease

7. Accessory Organs – Liver 1.(4) Lobes – Falciform ligament 2.Lesser Omentum and Lesser Curvature of Stomach 3. Hepatic Artery/Hepatic Portal Vein – Porta hepatis

8. Liver – Histology 1.Liver lobules – hepatocytes 2.Portal Triads 3.Sinusoids 4.Hepatocyte Functions – bile production – glucose-glycogen – store fat-soluble vitamins – detoxification 5. Hepatitis

9. Liver – Digestion 1.Bile and Bile Salts – emulsify fats – fat and cholesterol absorption 2.Reabsorption of Bile Salts – Enterohepatic circulation – Reabsorbed into the blood via ileum; liver-hepatic portal blood 3.Bilirubin – hemoglobin heme (waste product of heme) – liver cell absorption and excreted into bile – Sterocobilin

10. Gall Bladder 1.Stores Bile 2.Structure and Histology – Simple Columnar Epithelium – rugae 3.Contraction – cystic duct -----  bile duct – released into duodenum 4. Regulation – CCK

11. Bile Regulation

12. Large Intestine – Gross Anatomy

13. Large Intestine – Histology 1. Mucosa – simple columnar – No absorption 2. Anal Canal – stratified squamous 3. Venous Plexuses – Hemorrhoids 4. Bacterial Flora – 10 million – Roles and functions – Vitamin K – Bacteria and digestive functions

14. Large Intestine – Various 1. Motility – Mass Movements 2. Defecation – Reflex

15. Absorption of Nutrients 1. 80% - Small Intestine – Ileum 2. Active Transport – Capillaries ----  hepatic portal vein ----  liver – Lipids and lacteals 3. Simple Columnar Epithelium