Digestive System Anatomy & Physiology Digestive Processes Digestive Organs Mesentary Peritonitis Oral Anatomy Lateral View Cadaver Midsaggital Section of Oral Structures Oral Anatomy Anterior View Tongue Anatomy Taste Bud Anatomy Salivary Glands Cadaver ___ Gland Tooth Anatomy Tooth Eruption Impacted Molar Gingiva Universal Tooth Numbering System Tooth Faces • Lingual (Nearest Tongue) • Facial (Farthest from tongue) • Mesial (Closest to the incisors) • Distal (Farthest from the incisors • Occlusal (Grinding surface Splanchnic Circulation 25% of Cardiac Output Endoscope Larynx Esophageal Reflux G.E.R.D. (GastroEsophageal Reflux Disease) Gastric Fundus Gastritis due to Helicobacter Pylori Gastric Diverticulum Gastric Polyps Gastric Carcinoma Duodenal Mucosa Duodenal Ulcer Proctologist Testing for Occult Blood Colonoscopy Colonoscopy Administration Caecal Diverticula Descending Colon Tapeworms Ulcerative Colitis (Sigmoid Colon & Rectum) Rectum Anal Hemorrhoids (Piles) Caused by Inflammation of the Superior & Inferior Hemorrhoid Veins Scope Comparison Barium Enema Colostomy & Stoma Colostomy Bag Peristalsis 27 Year Old Male 81 Year Old Male Swallowing Gastric Regions Gastric Anatomy Gastric Cells Gastric Cell FXN’s • Goblet cells – produce alkaline mucus • Mucus Neck cells – produce acidic mucus • Parietal cells – produce HCl & Intrinsic Factor • Chief cells – produce pepsinogen • Enteroendocrine cells – produce gastrin, pepsin, cholecystokinin, & somatostatin Gall Bladder & Pancreas Empty Contents into Duodenum Liver & Pancreas Secretions Liver FXN’s • Synthesizes bile (bile salts, biliruben, & cholesterol) • Stores glucose as glycogen • Stores fat soluble vitamins ADEK Gall Bladder FXN • Stores bile • CCK contracts gall bladder secretion of pancreatic juice & relaxation of the sphincter of Oddi Pathophysiology • Gall stones – too much cholesterol or too few bile salts resulting in cholesterol crystal accumulation • Obstructional jaundice – bile duct becomes obstructed & bilirubin increases in blood Gallstones Bile Salt FXN Pancreas • Secretes basic pancreatic juice (pH 7.5-8.0) Pancreatic Juice (p.j.) • Bicarbonate rich p.j. neutralizes HCl in the duodenum (Stimulated by secretin when HCl enters the duodenum) • Enzyme rich p.j. stimulated by CCK when fatty or protein rich foods enter the duodenum Note • Hormones released in inactive form so they don’t digest the pancreas Accessory Organ Ducts & Sphincter HCO3- Na+ Pancreatic duct H 2O CO2 Pancreatic acinar cell H2CO3 Na+ H+ Blood capillary Pancreatic secretion of NaHCO3 (sodium bicarbonate) [simplified] Water & Mineral Digestion Absorption of… Vitamins – • A,D,E,K fat soluble (diffuse into blood) • B & C water soluble (diffuse into blood) • B12 requires intrinsic factor for diffusion…leads to pernicious anemia • Electrolytes (Na+, K+, HCO3-, Cl-) • Iron – binds to ferratin in mucosal cells & transferrin in the blood for transport • Calcium – PTH increases ionic calcium & vitamin D aids in absorption Lipid Emulsification Lipid Digestion Carbohydrate Digestion Na/K Symport Protein Digestion Brush Border Villi Small Intestine Large Intestine with Mesentery Cecum Anal Sphincter Control Hormonal Control of Digestion (Produced in stomach) • • • • Gastrin - HCl secretion & gastric emptying Serotonin – Contracts gastric muscle Histamine – HCl release from parietal cells Pepsinogen – inactive form of pepsin (HCl activated) • Somatostatin – Inhibits: gastric secretions gastric emptying pancreatic secretions intestinal absorption gall bladder contraction (bile release) catabolyzes protein Hormonal Control of Digestion (Produced in Duodenum) • Secretin - pancreatic juice secretion & bile output • Cholecystokinin - pancreatic juice output, contracts gall bladder, & relaxes sphincter of Oddi • Gastric inhibitory peptide – inhibits gastric secretion & motility • Vasoactive intestinal peptide – dilates intestinal capillaries & inhibits HCl production Hormonal Control of Digestion (Produced by pancreas) • Trypsinogen – Inactive form of trypsin (activated by enterokinase) catabolyzes protein to peptides • Amylase – catabolyzes polysaccharides • Lipase – catabolyzes lipids • Carboxypeptidase – catabolyzes protein to amino acids • Chymotrypsin – catabolyzes protein to peptides The absorptive state Metabolic states •During & for several hours after a meal •Insulin • glucose uptake by cells (from blood) • glycogenesis in liver cells • lipogenesis in fat cells • lipolysis in fat cells Continues until . . . Metabolic states The postabsorptive state •Begins several hours after a meal •Glucagon • glycogenolysis • gluconeogenesis • lipolysis in fat cells • lipogenesis in fat cells Feces may indicate health issues •Motility / timing •Diarrhea •Constipation •Color / consistency •Gray = lack of bile •Black/tarry = bleeding (upper) •Black = PeptoBismol •Red = bleeding (lower) Digestion of Alcohol