Reading Guided - The Digestive System I 1. "Traveler's diarrhea" results when A. enterogastrone secretion is inhibited. B. gastrointestinal motility is stimulated by increased parasympathetic outflow. C. guanylin receptors in the ileum and colon are stimulated by enterotoxins. D. cholecystokinin secretion is inhibited. 2. The first of the three phases of extrinsic control of gastric function is the gastric phase. True False 3. Which of the following is NOT a function of the stomach? A. store food B. kill bacteria C. digestion of most foods D. move chyme into the duodenum 4. Which of the following processes is NOT a liver function? A. lipogenesis B. gluconeogenesis C. hydrolysis of sucrose D. glycogenolysis 5. The combination of chewed food and saliva is called A. chyme. B. a bolus. C. pylorus. D. hiatal. 6. Which tunic of the GI tract is very vascular and has many nerves and glands? A. mucosa B. submucosa C. muscularis D. serosa 7. The intrinsic regulation of the GI tract is conferred by the autonomic nervous system. True False 8. __________ is a condition in which large number of liver lobules are destroyed and replaced by permanent, scar-like connective tissue. A. Jaundice B. Hepatitis C. Cholecystitis D. Cirrhosis
9. The conjugation of nonpolar compounds in the liver makes them _____ and water _____. A. polar; soluble B. polar; insoluble C. cationic; soluble D. cationic; insoluble 10. Wavelike muscular contraction of the gastrointestinal tract is called A. peristalsis. B. segmentation. C. deglutition. D. mastication. 11. What is the function of enterokinase secreted by the brush border? A. activates the protein-digesting enzyme trypsin B. breaks down dipeptides C. causes the stomach to produce gastrin D. causes release of pancreatic digestive enzymes 12. What allows the intestinal microbiota to live in the large intestine? A. protection by innate and adaptive immune systems B. the anaerobic environment C. availability of nutrients D. All of the choices are correct. 13. Normal levels of intestinal microbiota help protect us from pathogenic bacteria. True False 14. Active transport of Na+ into intestinal cells allows the osmosis of water. True False 15. Mutating the gene encoding for the H+/K+ ATPase would block gastric HCl secretion. True False 16. Excess use of antibiotics can kill the normal intestinal microflora, increasing inflammation by pathogenic bacteria. True False 17. Somatostatin is produced in the stomach by A. goblet cells. B. parietal cells. C. G cells. D. D cells. 18. A _____________ has the following pattern of circulation: capillaries -> veins -> capillaries -> veins. A. portal system B. sinusoid C. lobule D. glomerulus
19. What commonly ingested substances are absorbed through the stomach wall? A. water and alcohol B. antacid and water C. alcohol and aspirin D. penicillin and aspirin 20. Colipase is secreted by the duodenum and functions in fat emulsification. True False 21. Converting glucose into glycogen is the process of A. glycogenesis. B. glycogenolysis. C. gluconeogenesis. D. lipogenesis. 22. _________________ is a disorder in which acidic gastric juice travels up the esophagus. A. Gastroenteritis B. Gastroesophageal reflux disease C. Pernicious anemia D. Gastritis 23. Inhibiting the actions of the parietal cells would stimulate protein digestion. True False 24. Which is NOT true of conjugated bilirubin? A. bilirubin is combines with glucuronic acid B. it is not water soluble C. it is converted into urobilirubin in the intestine D. it is produced in the liver 25. The enterohepatic circulation is between the _____ and _____. A. liver, stomach. B. liver, pancreas. C. liver, intestine. D. liver, gallbladder.
Guided Reading - The Digestive System II
1. Exopeptidases include A. trypsin. B. aminopeptidase. C. elastase. D. chymotrypsin. 2. An important function of the liver is producing ketone bodies from fatty acids. True False 3. Clotting factors are produced by the A. liver. B. pancreas. C. stomach. D. duodenum. 4. Free amino acids are absorbed into the blood stream by A. simple diffusion. B. cotransport with H+. C. facilitated diffusion. D. cotransport with Na+. 5. The first line of defense in the stomach against damaging acid and pepsin is the A. tight junctions of epithelial cells. B. rapid rate of epithelial cell replacement. C. adherent layer of mucus. D. release of gastrin. 6. Bile is produced by the gallbladder. True False 7. Enterogasterone will _____ gastric function. A. stimulate B. inhibit C. have no effect on 8. Fats are digested into fatty acids and glycerol. True False 9. What structure keeps food from entering the larynx during swallowing? A. epiglottis B. laryngopharynx C. soft palate D. tongue
10. Slow wave depolarization triggers depolarization of smooth muscle by opening voltage--gated ________ channels. A. K+ B. Na+ C. Ca2+ D. Ach 11. Vitamin B12 is primarily absorbed in the A. duodenum. B. jejunum. C. ileum. D. cecum. 12. The __________ stimulates decreased gastric motility. A. gastroileal reflex B. GLP-1 reflex C. ileogastric reflex D. GIP reflex 13. The intestinal microbiota have a mutualistic relationship with humans. True False 14. Protein digestion would decrease if lactase were not present on the brush border. True False 15. The superior portion of the esophagus contains smooth muscle in its wall. True False 16. What is the function of Paneth cells of the small intestine? A. produce mucus B. divide by mitosis to make new mucosa cells C. produce lysozyme and antimicrobial peptides D. produce digestive enzymes 17. The brush border is a term used to describe the mucosa of the small intestine. True False 18. The outer surface bulges of the large intestine are called A. crypts. B. cecum. C. haustra. D. colon. 19. Secretin stimulates chief cells to secrete pepsinogen. True False
20. ___________ is a principal bile acid. A. Chenodeoxycholic acid. B. Lactic acid. C. Uric acid. D. Both lactic acid and uric acid. 21. What substance is necessary for the hydrolysis of complex food molecules? A. specific enzyme B. acid C. water D. Both a specific enzyme and water are correct. 22. Stress would cause GI motility and secretions to be A. increased. B. decreased. C. unchanged. 23. Excessive amounts of porphyrin heme groups in the liver is toxic and called porphyria. True False 24. Venous and arterial blood mix in a liver lobule. True False 25. Which of the following is NOT true of 5-hydroxytryptamine? A. it is secreted by ECL cells of the intestinal mucosa B. stimulates intrinsic afferent to activate motor neurons for peristalsis C. stimulates secretion of Cl- and water D. All of the choices are not true.
Guided Reading - The Digestive System III 1. ____________ is required for the intestinal absorption of vitamin B12. A. Vitamin D B. Calcium C. Intrinsic factor D. Vitamin C 2. Acid chyme is buffered by __________ secreted from the pancreas. A. mucus B. bicarbonate C. ammonia D. urea 3. Pepsin would not be found in the stomach if the __________ cells were destroyed. A. goblet B. parietal C. D cells D. chief or zymogenic 4. __________ is secreted by the ileum and colon and stimulates intestinal secretion of Cl- thereby causing elimination of NaCl and water in the feces. A. Guanylin B. Motilin C. Serotonin D. Nitric oxide 5. The ______ stimulates increased gastrin activity and increased movement of chyme into the duodenum. A. gastroileal reflex B. GLP-1 reflex C. ileogastric reflex D. GIP reflex 6. Secretion of insulin from the pancreas is increased in response to A. increased secretin. B. increased GIP. C. increased guanylin. D. increased gastrin. 7. The movement of digested food into the blood or lymph is A. ingestion. B. deglutition. C. absorption. D. segmentation.
8. Bile pigment is a derivative of A. heme group without iron B. iron C. globin part of hemoglobin D. cholesterol 9. During the intestinal phase regulating gastric function A. the vagus nerve stimulates gastrin secretion. B. stomach distension stimulates acid secretion. C. vagal nuclei are stimulated by smelling food. D. gastric emptying is inhibited. 10. The majority of hydrolysis of disaccharides occurs by the actions of enzymes found A. in the pancreatic juice. B. in the brush border of the small intestine. C. in saliva. D. in the gastric mucosa. 11. Damage to which tunic of the GI tract would directly affect Auerbach's plexus? A. mucosa B. submucosa C. muscularis D. serosa 12. Aldosterone affects salt and water absorption in the intestine. True False 13. Which of the following is NOT true about CCK (cholecystokinin)? A. released in response to fat and protein in the chyme B. stimulates the production of pancreatic digestive enzymes C. uses cyclic AMP as the second messenger to pancreatic acinar cells D. controlled through a positive feedback loop 14. Very-low-density lipoproteins are produced by the liver. True False 15. The enzymes for digestion of carbohydrates come from all of the following EXCEPT the A. pancreas. B. duodenum. C. liver. D. salivary glands. 16. Low-density lipoproteins functions to remove and degrade cholesterol. True False 17. ____________ are hepatic phagocytic cells of the reticuloendothelial system. A. Hepatocytes B. Kupffer cells C. Langerhan cells D. Merkel's cells
18. Which of the following may be beneficial in treating gastric ulcers? A. epinephrine B. histamine blockers C. gastric inhibitory peptide D. carboxypeptidase 19. Place the tunics of the GI tract wall in the correct order from superficial to deep. A. submucosa, mucosa, serosa, muscularis B. mucosa, muscularis, submucosa, serosa C. serosa, submucosa, mucosa, muscularis D. serosa, muscularis, submucosa, mucosa 20. Mutation of the gene encoding for cholecystokinin would limit pancreatic bicarbonate secretion. True False 21. Anemia often results due to a lack of intrinsic factor. True False 22. The appendix is a short, thin out-pouching of the ileum. True False 23. Histamine release will cause more acid to be released in the stomach. True False 24. Drugs such as Zantac and Tagamet help treat gastritis and ulcers by A. blocking H2--histamine receptors. B. blocking H1--histamine receptors. C. inhibiting proton pumps. D. killing bacteria. 25. Which of the following is NOT an effect of CCK? A. stimulates secretion of water and bicarbonate rich pancreatic juice B. stimulates contraction of the gall bladder C. inhibits gastric motility D. stimulates secretion of pancreatic juice rich in enzymes
Guided Reading - The Digestive System IV
1. Which of following the motility processes is NOT correctly matched to its description? A. peristalsis - rhythmic, wave-like contractions B. mastication - removal of wastes C. ingestion - taking food into the mouth D. deglutition - swallowing 2. What structure keeps food from exitting from the nose during swallowing? A. epiglottis B. nasopharynx C. soft palate D. tongue 3. The enzyme with the most basic pH optimum is A. pancreatic lipase. B. pepsin. C. maltase. D. salivary amylase. 4. Which of the following zymogens is activated by trypsin in the small intestine? A. lipase B. carboxypeptidase C. ribonuclease D. amylase 5. Lipid digestion and absorption requires the coordinated actions of ______ and ____. A. hydrochloric acid, pepsin. B. bile, bicarbonate. C. lipase, bile. D. water, bile. 6. Where does the bicarbonate secreted by the pancreas come from? A. bicarbonate in the blood B. CO2 in the blood C. acini cells D. pancreatic islets 7. The gastrointestinal tract generates monomers from polymers by condensation. True False 8. Digestion of starch starts in the stomach. True False 9. Sensory neurons within intestinal plexuses that travel in the vagus to the CNS are called A. extrinsic afferents. B. intrinsic afferents. C. paracrine regulators. D. myenteric afferents.
10. Most protein digestion occurs in the A. mouth and esophagus. B. stomach and duodenum. C. duodenum and jejunum. D. pancreas and duodenum. 11. Absorbed lipids are initially transported by the lymphatic system. True False 12. ___________ are large capillary spaces separating hepatic plates. A. Hepatocytes B. Lobules C. Sinusoids D. Portal systems 13. Bile is produced by A. Kupffer cells. B. gall bladder cells. C. hepatocytes. D. sinusoids. 14. Which of the following is one of the phases of swallowing? A. pharyngeal B. peristalsis C. reflux D. segmentation 15. The lining of the intestine provides a physical barrier against microorganisms and their toxins. True False 16. Paracrine regulators are part of the extrinsic regulation of the GI tract. True False 17. Histamine secretion by the stomach would be prevented by destruction of the A. D cells. B. G cells. C. chief cells. D. enterochromaffin-like cells. 18. Bicarbonate that protects the duodenum from peptic ulcers comes from all of the following EXCEPT: A. adherent layer of mucus B. Brunner's cells C. stomach D. pancreatic juice 19. What provides intrinsic regulation of the GI tract? A. hormones B. autonomic nervous system C. enteric nervous system D. All of the choices are correct.
20. The _________________ of the stomach and intestine secrete histamine and serotonin. A. G cells B. parietal cells C. enterochromaffin-like (ECL) cells D. chief cells 21. The mucosa of the esophagus is A. stratified cuboidal epithelium. B. pseudostratified columnar epithelium. C. simple columnar epithelium. D. nonkeratinized stratified squamous epithelium. 22. Which of the following is NOT a major constituent of bile? A. cholesterol B. bilirubin C. urea D. lethecin 23. The vagus nerve stimulates gastrin secretion during the cephalic phase of gastric function. True False 24. What role do biles salts play in digestion? A. emulsify lipids for digestion by enzymes B. gives color to the feces C. needed for water reabsorption D. They play no role in digestion. 25. Protection against atherosclerosis is believed to be associated with an A. elevated HDL-cholesterol. B. elevated LDL-cholesterol. C. elevated total cholesterol. D. elevated VLDL-cholesterol.
Guided Reading - The Digestive System V
1. Cholesterol produced by the body is transported in the blood as A. high-density. B. low-density. C. very low-density. D. medium-density. 2. Chylomicrons are combinations of lipid and protein formed in intestinal epithelial cells. True False 3. Increased production of cytochrome P450 enzyme to break down hormones and drugs is mediated through the stimulation of what kind of receptor? A. specific anion receptor B. SXR receptor C. enterogastrone receptor D. enterokinase receptor 4. Sympathetic nerve fibers can cause the release of HCl from parietal cells. True False 5. What structures supplies autonomic nerves to the muscularis tunic? A. Meissner's plexus B. Auterbach's plexus C. myenteric plexus D. Both Auterbach's plexus and myenteric plexus are correct. 6. Why does the upper third of the esophagus have skeletal muscle in its wall? A. so you do not choke B. the first phase of swallowing is voluntary C. so that peristalsis can occur D. the first phase of swallowing is involuntary 7. Aminopeptidase and carboxypeptidase are classified as endopeptidases. True False 8. Which of the following is NOT a barrier to acid and pepsin damage in the stomach? A. adherent layer of mucus B. bicarbonate C. gap junctions between epithelial cells D. rapid turnover of epithelial cells 9. Which of the following is NOT a structure of the small intestine that increases its surface area? A. rugae B. villi C. plicae circularis D. microvilli
10. Helicobacter pylori is a bacterium associated with A. peptic ulcers. B. hiatal hernia. C. acid reflux. D. pancreatitis. 11. Amino acids and peptides in the stomach lumen stimulate acid secretion during the ________ phase of gastric secretion. A. gastric B. cephalic C. hepatic D. intestinal 12. Peristalsis is regulated by the A. sympathetic nervous system. B. parasympathetic nervous system. C. enteric nervous system. D. somatic nervous system. 13. Micelles, made of biles salts, have hydrophilic and hydrophobic regions that allow them to emulsify fats and dissolve in water. True False 14. GI tract hormones affect the organs that secrete them. True False 15. Antihistamines would limit the gastric secretion of A. pepsinogen. B. gastrin. C. hydrochloric acid. D. mucus. 16. Triglycerides are remade in intestinal epithelial cells before combining with proteins to form chylomicrons. True False 17. Damage to which of the following nerves would reduce GI secretions? A. glossopharyngeal nerve B. hypoglossal nerve C. vagus nerve D. phrenic nerve 18. Atrophy of the pancreatic acinar cells occurs in response to A. increased gastrin secretion. B. decreased sympathetic stimulation. C. decreased cholecystokinin secretion. D. increased secretin secretion.
19. In which of the following areas does carbohydrate digestion occur? A. mouth and stomach B. duodenum and pancreas C. stomach and pancreas D. mouth and duodenum 20. Inhibiting hepatic function has no effect on blood clotting. True False 21. GIP both inhibits gastric motility and increases the release of insulin from the pancreas. True False 22. H+/K+ ATPase pumps transport H+ against its concentration gradient out of the lumen of the stomach while transporting K+ in the opposite direction. True False 23. The stomach churns food into a pasty material called A. a bolus. B. chyme. C. chyle. D. saliva. 24. Zymogens are inactive forms of __________ enzymes. A. stomach B. liver C. pancreatic D. small intestine 25. Pepsin would have the greatest activity A. immediately upon secretion into the stomach. B. immediately upon entering the duodenum. C. when the pH of the chyme is greater than 3. D. when the pH of the chyme is less than 3.
Guided Reading - The Digestive System VI
1. Pernicious anemia develops if there is a vitamin ________ deficiency. A. C B. B6 C. B12 D. D 2. __________ stimulates ECL cells to secrete histamine which stimulates HCl release from parietal cells. A. Secretin B. CCK C. Gastrin D. Ghrelin 3. Which of the following gastrointestinal hormones is NOT secreted by the small intestine? A. secretin B. gastric inhibitory peptide C. gastrin D. cholecystokinin 4. As bile is produced, it drains into A. bile canaliculi. B. hepatic veins. C. the central vein. D. sinusoids. 5. The acidic chyme entering the duodenum initiates all of the following actions EXCEPT: A. the intestinal phase of gastric function B. the release of serotonin from the duodenum C. the release of bicarbonate from the pancreas D. the release of bicarbonate into bile 6. Absorptive cells of the gastrointestinal tract are located within the mucosa. True False 7. Which of the following is NOT a function of intestinal microbiota? A. production of B vitamins B. ferment indigestible contents of the chyme C. production of vitamin K D. hydrolyze proteins 8. Which of the following is NOT produced by the liver? A. hydroxylated steroid hormones B. uric acid C. digestive enzymes D. bilirubin 9. The liver will detoxify ammonia by converting it into A. uric acid. B. ammonium ions. C. urea. D. amino acids.
10. Bile is forced up the cystic duct through the closing of the A. sphincter of Oddi. B. lower esophageal sphincter. C. pyloric sphincter. D. ileocecal valve. 11. Most of the food is digested and absorbed through the wall of the stomach. True False 12. Blood from the digestive organs enters general circulation and eventually reaches the liver for processing. True False 13. Exocrine secretions of the digestive system include enzymes and bicarbonate. True False 14. Which of the following is NOT part of the gastrointestinal tract? A. pharynx B. liver C. small intestine D. esophagus 15. Slow waves of the intestine are conducted through what type of cells? A. gastric cells B. microflora cells C. SXR Cells D. Cajal cells 16. Parasympathetic antagonists would stimulate gastrointestinal motility. True False 17. Gastric hydrochloric acid secretion is regulated through both negative and positive feedback mechanisms. True False 18. The primary function of the large intestine is A. water and electrolyte reabsorption. B. mineral absorption. C. hormone degradation. D. degrading toxins. 19. Chewing of food is A. deglutition. B. mastication. C. peristalsis. D. segmentation. 20. Diarrhea often results when the osmolarity of the fecal matter in the colon is increased. True False
21. Secretion of enterogasterone is stimulated by _____ in the chyme. A. protein B. acid C. glucose D. fats 22. Inhibition of exocrine pancreatic secretions results in A. decreased insulin secretion following meals. B. decreased bile synthesis and secretion. C. production of an acidic chyme. D. stimulation of enterokinase activity. 23. The major stimulus for the secretion of HCl during the cephalic phase of gastric regulation is A. the smell of food. B. vagal stimulation of chief cells. C. release of histamine by ECL cells. D. vagal stimulation of parietal cells. 24. Bile salts are derivatives of A. sodium chloride. B. hemoglobin. C. bilirubin. D. cholesterol. 25. Bile is derived from cholesterol. True False