Quiz 3 Study Guide - BIOL 431 Hybrid PDF

Fajardo QUIZ 3 STUDY GUIDE Digestive System: ML&M Ch 23, TopHat Unit 24 Alimentary canal/gastrointestinal (GI) tract/digestive tract/gut ○ Digests food ○ Absorbs nutrients ○ Open to outside Accessory organs...

Fajardo QUIZ 3 STUDY GUIDE Digestive System: ML&M Ch 23, TopHat Unit 24 Alimentary canal/gastrointestinal (GI) tract/digestive tract/gut ○ Digests food ○ Absorbs nutrients ○ Open to outside Accessory organs ○ Teeth ○ Tongue ○ Gallbladder ○ Glands Salivary glands Liver Pancreas Digestive processes ○ Ingestion ○ Mechanical breakdown ○ Propulsion Swallowing (deglutition) Peristalsis Segmentation ○ Digestion 3 majors steps: Mechanical and chemical stimuli detected by receptors in GI tract SmM and glands stimulated to take action Neurons: reflexes; hormones affect digestive actions ○ Absorption ○ Defecation Peritoneum ○ Mesentery Omenta (greater omentum, lesser omentum) Transverse mesocolon ○ Retroperitoneal vs peritoneal definitions Major digestive organs of the alimentary canal ○ Mouth (where it all starts) Stratified squamous epithelium Ingestion & mastication Salivary Amylase Palate (hard & soft) Uvula Vestibule Gingivae Labial frenula (s. Labial frenulum) Fajardo ○ Pharynx Nasopharynx (NOT part of swallowing) Oropharynx laryngopharynx ○ Esophagus Mucosa: Stratified squamous epithelium Submucosa Muscularis externa Adventitia Lumen usually closed Gastroesophageal sphincter/lower esophageal sphincter/cardial sphincter Fig 23.14. Deglutition (swallowing) process (5 steps) Buccal phase Pharyngeal esophageal phase Pharyngeal esophageal phase Peristalsis Gastroesophageal sphincter (what happens when this sphincter does not work well?) ○ Stomach Cardia Fundus Body Pyloric parts (pylorus) Pyloric antrum Pyloric canal Pyloric sphincter/valve Greater curvature Lesser curvature Rugae (folds of the mucosa) Muscularis externa has an additional layer: oblique layer Produces chyme Histology Gastric pits Gastric glands Parietal cells ○ HCl ○ Intrinsic factor Chief cells: pepsinogen (and a little bit of lipases) ○ Pepsinogen → pepsin reaction ○ Pepsin enzyme function Enteroendocrine cells ○ Gastrin ○ Histamine ○ & others - see textbook Fajardo Gastric ulcer ○ H. pylori bacteria Mechanical processes of stomach Regulation of digestive activities Gastric secretions (neural and hormonal controls) ○ Cephalic phase ○ Gastric phase ○ Intestinal phase Gastric motility & emptying ○ Stretch ○ Peristalsis ○ Duodenum ○ What you ate ○ Small intestine Duodenum Jejunum Ileum Circular folds Villi Microvilli (Brush border) Brush border enzymes Histology: Enterocytes Goblet cells Enteroendocrine cells Paneth cells ○ Intestinal crypts Stem cells Lymphatic system: MALT/peyer’s patches; lacteals Digestive activities of the small intestine Regulation of small intestine activities Chyme entry Motility ○ Large intestine Ileocecal valve Cecum Appendix Colon Tenia coli Haustra Ascending colon Transverse colon ○ Transverse mesocolon Descending colon Fajardo Sigmoid colon Rectum Anus ○ Internal anal sphincter ○ External anal sphincter Histology Thick mucosa Big crypts with many goblet cells (lots of mucus) Bacterial microbiota ○ Fermentation ○ Vitamin synthesis ○ Keep pathogens at bay and assisting balancing the immune system Processes of movement Segmentation Peristalsis ○ Mass movements Defecation ○ 3 steps from fig 23.35 Accessory organs of the digestive system ○ Accessory organs of the mouth Tongue tastebuds Teeth deciduous/milk/baby/primary teeth Permanent teeth ○ Incisors ○ canines/eyetooth/cuspids ○ bicuspids/premolars ○ Molars Enamel Dentin Pulp Crown Root Neck Gingiva Lips & cheeks Salivary glands Parotid salivary gland Sublingual salivary gland Submandibular salivary gland ○ Liver & gallbladder. Liver: many functions. Digestive function: produces bile. Gallbladder: storage of bile Fajardo Lobes of the liver (Right, Left, caudate, quadrate) Falciform ligament (not really a ligament) Bare area Liver lobules Portal triad ○ Bile duct Bile manufactured by hepatocytes, transport bile through bile canaliculi, bile sent to bile duct Bile pigments (e.g. bilirubin) Bile salts Recycling of bile salts (enterohepatic circulation) phospholipids ○ Portal vein ○ Portal arteriole Central vein Liver sinusoids Gallbladder Cystic duct Homeostatic imbalances of the liver & gallbladder Hepatitis ○ Viruses ○ Alcohol, drugs, wild mushrooms ○ Non-alcoholic fatty liver disease (NAFLD) Cirrhosis Gallstones Jaundice ○ Pancreas Acini (s. acinus) with acinar cells → enzymes (these are just examples/broad classes of enzymes. There are specific examples in the text and in the lecture) Proteases Amylase Lipases Nucleases **enzymes are usually released in their inactive form and are activated in small intestine** Duct cells ○ Ducts of the accessory organs leading into the small intestine: R and L hepatic ducts (Liver) Common hepatic duct (liver) Cystic duct (gallbladder) Bile duct (bile from liver and gallbladder) Main pancreatic duct Fajardo Hepatopancreatic ampulla & sphincter Major duodenal papilla CCK, secretin aid in regulating digestive enzyme, bile, bicarbonate release from accessory organs Physiology of digestion & absorption ○ Carbohydrates Salivary amylase Pancreatic amylase Brush border enzymes Dextrinase Glucoamylase Maltase Sucrase Lactase ○ Lactose intolerance Poly-, oligo-, disaccharides vs monosaccharides (polymer vs monomer) Transport of monosaccharides into enterocytes Exit of monosaccharides from enterocytes into blood / body tissues ○ Proteins Pepsinogen → pepsin Pancreatic proteases (trypsin, chymotrypsin) Carboxypeptidases Brush border enzymes Aminopeptidases, carboxypeptidases, dipeptidases Amino acids (monomer) transport into and out of enterocytes and into blood ○ Lipids Lipases found throughout digestive tract Emulsification with bile salts Digestion with pancreatic lipase Micelle formation Diffusion into enterocytes Chylomicron formation & transport Lipoprotein lipase ○ Absorption of vitamins ○ Absorption of electrolytes Na+, Cl-, HCO3- K+ Iron Ca2+ ○ Absorption of water