front 1 On the epithelial surface of most of the gastrointestinal tract, the billions of single-cell mucous glands are called: A. Chief cells | back 1 C. Goblet cells |
front 2 In the small intestine, epithelial pits formed by invagination are known as: A. Gastric rugae | back 2 B. Crypts of Lieberkühn |
front 3 Large numbers of deep tubular glands are especially found in the: A. Esophagus and ileum | back 3 D. Stomach and upper duodenum |
front 4 The presence of food in one GI segment usually causes glands of that region and nearby regions to secrete: A. Minimal acidic fluid | back 4 B. Moderate to large juices |
front 5 Which local stimulus can activate the enteric nervous system to promote glandular secretion? A. Tactile stimulation | back 5 A. Tactile stimulation |
front 6 Which local factor is specifically listed as a trigger of enteric reflex secretion? A. Hypoglycemia | back 6 B. Gut wall distention |
front 7 Which of the following is another listed epithelial stimulus for local glandular activation? A. Chemical irritation | back 7 A. Chemical irritation |
front 8 The nutrient material used to form glandular secretions first enters which part of the secretory cell? A. Apical membrane | back 8 C. Cell base |
front 9 Nutrient material for secretion reaches glandular cells directly from blood in the: A. Lacteals | back 9 B. Capillaries |
front 10 Many mitochondria are concentrated near the base of glandular cells primarily to generate: A. NADPH | back 10 D. ATP |
front 11 The organic secretory substances are synthesized primarily in the: A. Lysosome | back 11 C. Endoplasmic reticulum |
front 12 ATP and nutrient-derived substrates are used for synthesis in the endoplasmic reticulum and: A. Golgi complex | back 12 A. Golgi complex |
front 13 In the Golgi complex, secretory materials are modified, concentrated, and packaged into: A. Ribosomal subunits | back 13 B. Secretory vesicles |
front 14 Before release, secretory vesicles are stored in which region of the cell? A. Basal cytoplasm | back 14 D. Apical end |
front 15 Nervous or hormonal signals cause glandular cells to release stored vesicle contents by: A. Pinocytosis | back 15 C. Exocytosis |
front 16 Mucus is composed mainly of water, electrolytes, and: A. Bile pigments | back 16 B. Glycoproteins |
front 17 The ability of mucus to coat surfaces effectively depends in part on its tendency to adhere: A. Loosely to epithelium | back 17 B. Tightly to particles |
front 18 Which physical property of mucus most directly allows luminal particles to slide easily along epithelium? A. High surface tension | back 18 B. Low slippage resistance |
front 19 In the colon, mucus most directly helps bowel movements by causing fecal particles to: A. Dissolve into chyme | back 19 C. Adhere to one another |
front 20 A patient with impaired mucus quality develops increased luminal enzyme injury. Which normal mucus property is most protective here? A. Strong enzyme resistance | back 20 A. Strong enzyme resistance |
front 21 Mucus commonly contains which ion that helps neutralize acids? A. Chloride | back 21 C. Bicarbonate |
front 22 Which set correctly lists the four principal salivary glands named in this material? A. Parotid, buccal, pyloric, Brunner | back 22 C. Parotid, submandibular, sublingual, buccal |
front 23 Saliva contains a serous secretion with which starch-digesting enzyme? A. Pepsin | back 23 B. Ptyalin |
front 24 Ptyalin is best classified as a: A. Lipase | back 24 C. α-amylase |
front 25 The mucus component of saliva contains which substance primarily responsible for lubrication and protection? A. Elastin | back 25 B. Mucin |
front 26 Which salivary gland secretes almost entirely a serous product? A. Sublingual | back 26 D. Parotid remember serous is enzyme-rich, watery. mucus is protein-rich, thick |
front 27 Which glands secrete both serous secretion and mucus? A. Parotid and buccal | back 27 B. Submandibular and sublingual |
front 28 A biopsy from a GI secretory cell shows intense protein synthesis followed by packaging and concentration of product before release. Which organelle pair is most responsible? A. Nucleus and lysosome | back 28 B. ER and Golgi |
front 29 A local meal-induced reflex increases secretion in a GI segment and nearby regions. This response is most directly attributed to activation of the: A. Sympathetic chain | back 29 B. Enteric nervous system |
front 30 A protective surface secretion forms a thin film over food and mucosa while resisting enzymatic digestion. Which secretion is being described? A. Bile | back 30 C. Mucus |
front 31 Which salivary glands secrete only mucus? A. Parotid glands | back 31 B. Buccal glands |
front 32 The salivary secretion process is best described as a two-stage operation involving: A. Acini, then salivary ducts | back 32 A. Acini, then salivary ducts |
front 33 Salivary flow helps protect the oral cavity primarily by washing away pathogenic: A. Fungi | back 33 D. Bacteria |
front 34 Besides microorganisms, saliva also helps remove which material that supports bacterial metabolism? A. Bile salts | back 34 B. Food particles |
front 35 Saliva often contains significant amounts of which protective factor that can destroy oral bacteria? A. Histamine | back 35 C. Antibodies |
front 36 In the absence of salivation, oral tissues most commonly become: A. Hyperkeratotic and painless | back 36 B. Ulcerated and infected |
front 37 Salivary glands are controlled mainly by which division of the autonomic nervous system? A. Sympathetic | back 37 B. Parasympathetic |
front 38 The main central origins of salivary parasympathetic output are the superior and inferior salivatory nuclei in the: A. Midbrain | back 38 C. Brain stem |
front 39 The salivatory nuclei are located near the junction of the: A. Midbrain and thalamus | back 39 B. Medulla and pons |
front 40 Which stimulus can excite the salivatory nuclei? A. Taste from tongue | back 40 A. Taste from tongue |
front 41 Which additional stimulus can excite the salivatory nuclei? A. Tactile oral stimulation | back 41 A. Tactile oral stimulation |
front 42 Tactile stimuli reaching the salivatory nuclei arise from the tongue and other areas of the mouth and: A. Esophagus | back 42 C. Pharynx |
front 43 Salivation directly causes what vascular response in salivary glands? A. Venous constriction | back 43 B. Arteriolar dilation |
front 44 The vascular effect of salivation primarily serves to increase gland: A. Fibrosis | back 44 C. Nutrition |
front 45 The stomach mucosa contains two important types of tubular glands called: A. Brunner and Lieberkühn | back 45 B. Oxyntic and pyloric |
front 46 Oxyntic glands are also known as: A. Salivary glands | back 46 B. Gastric glands |
front 47 Which secretion is produced by oxyntic glands? A. Bile | back 47 C. Hydrochloric acid |
front 48 Oxyntic glands also secrete which zymogen? A. Pepsin | back 48 B. Pepsinogen |
front 49 Which additional product is secreted by oxyntic glands? A. Intrinsic factor | back 49 A. Intrinsic factor |
front 50 Oxyntic glands also secrete: A. Mucus | back 50 A. Mucus |
front 51 Pyloric glands secrete mainly which substance? A. Acid | back 51 B. Mucus |
front 52 The hormone secreted by pyloric glands is: A. Secretin | back 52 C. Gastrin |
front 53 The mucus from pyloric glands mainly protects the pyloric mucosa from: A. Bile reflux | back 53 B. Stomach acid |
front 54 Oxyntic glands are located primarily in the: A. Cardia and pylorus | back 54 B. Body and fundus |
front 55 Pyloric glands are located mainly in the: A. Fundus | back 55 C. Antral region |
front 56 Which cell type in oxyntic glands secretes mainly mucus? A. Parietal cells | back 56 B. Mucous neck cells |
front 57 Peptic cells are also called: A. Enterochromaffin cells | back 57 B. Chief cells |
front 58 Peptic cells secrete large quantities of: A. Pepsin | back 58 B. Pepsinogen |
front 59 Parietal cells are also called: A. Chief cells | back 59 C. Oxyntic cells |
front 60 Parietal cells secrete hydrochloric acid and: A. Gastrin | back 60 B. Histamine |
front 61 The main driving force for hydrochloric acid secretion by parietal cells is the: A. Sodium-calcium exchanger | back 61 B. Hydrogen-potassium pump |
front 62 A major component of the gastric barrier that limits acid backleak is: A. Acidic mucus | back 62 B. Alkaline mucus |
front 63 Another key component preventing gastric acid backleak is: A. Gap junctions | back 63 C. Tight junctions |
front 64 Parasympathetic acetylcholine stimulates peptic cells to secrete: A. Histamine | back 64 B. Pepsinogen |
front 65 Parasympathetic acetylcholine stimulates parietal cells to secrete: A. Hydrochloric acid | back 65 A. Hydrochloric acid |
front 66 Parasympathetic acetylcholine stimulates mucous cells to secrete: A. Histamine | back 66 C. Mucus |
front 67 Which two mediators strongly stimulate parietal cell acid secretion? A. Gastrin and histamine | back 67 A. Gastrin and histamine |
front 68 Pepsinogen is converted to active pepsin after contact with: A. Gastrin | back 68 C. Hydrochloric acid |
front 69 Parietal cells closely associate with which neighboring cell type? A. Goblet cells | back 69 B. ECL cells |
front 70 The primary function of Enterochromaffin-like cells is secretion of: A. Gastrin | back 70 C. Histamine |
front 71 A patient has impaired pepsinogen release from peptic cells despite normal gastric acidity. Loss of which signal would most directly explain this finding? A. Secretin | back 71 B. Acetylcholine |
front 72 Pepsinogen secretion by peptic cells is stimulated by acetylcholine and by: A. Acid in stomach | back 72 A. Acid in stomach |
front 73 Which sequence correctly lists the phases of gastric secretion? A. Gastric, cephalic, intestinal | back 73 B. Cephalic, gastric, intestinal |
front 74 A diner begins salivating and secreting gastric juice while chewing, before any swallowed food arrives. This is the: A. Intestinal phase | back 74 C. Cephalic phase |
front 75 The cephalic phase occurs before food enters the: A. Duodenum | back 75 B. Stomach |
front 76 A physiology lab infuses a meal directly into the stomach. Which phase of gastric secretion is now dominant? A. Intestinal | back 76 D. Gastric |
front 77 The gastric phase is initiated when what enters the stomach? A. Bile | back 77 C. Food |
front 78 Food entering the upper small intestine, especially the duodenum, triggers which phase of gastric secretion? A. Gastric | back 78 C. Intestinal |
front 79 The intestinal phase is associated especially with food in the: A. Ileum | back 79 B. Duodenum |
front 80 Trypsin and chymotrypsin digest proteins mainly into: A. Monosaccharides | back 80 D. Peptides |
front 81 Which statement best describes the action of trypsin and chymotrypsin? A. Release all free amino acids | back 81 B. Form peptides of varying sizes |
front 82 Which enzyme can split some peptides into individual amino acids? A. Elastase | back 82 C. Carboxypolypeptidase |
front 83 A patient lacks the enzyme that activates trypsinogen at the intestinal surface after chyme contacts mucosa. Which enzyme is deficient? A. Carboxypolypeptidase | back 83 B. Enterokinase |
front 84 Enterokinase is secreted by the: A. Intestinal mucosa | back 84 A. Intestinal mucosa |
front 85 Enterokinase release occurs when chyme comes into contact with the: A. Hepatic duct | back 85 C. Intestinal mucosa |
front 86 Which set contains the three major stimuli for pancreatic secretion? A. Histamine, gastrin, pepsin | back 86 B. Acetylcholine, CCK, secretin |
front 87 Which pancreatic stimulus is released from parasympathetic vagal endings? A. Cholecystokinin | back 87 C. Acetylcholine |
front 88 Cholecystokinin is secreted by the mucosa of the: A. Colon and rectum | back 88 B. Duodenum and upper jejunum |
front 89 Secretin is secreted by the mucosa of the: A. Duodenum and jejunum | back 89 A. Duodenum and jejunum |
front 90 Highly acidic food entering the small intestine most directly stimulates release of: A. Gastrin | back 90 C. Secretin |
front 91 Acetylcholine and CCK act primarily on which pancreatic cells? A. Acinar cells | back 91 A. Acinar cells |
front 92 Stimulation of pancreatic acinar cells by acetylcholine and CCK leads to secretion of large quantities of: A. Bicarbonate-rich water | back 92 B. Digestive enzymes |
front 93 Secretin primarily stimulates which pancreatic tissue? A. Islet tissue | back 93 C. Ductal epithelium |
front 94 Secretin causes secretion of a pancreatic fluid with high bicarbonate and low: A. Potassium | back 94 D. Chloride |
front 95 Secretin is released from which cells? A. I cells | back 95 B. S cells |
front 96 Release of CCK from I cells is promoted by proteoses, peptones, and: A. Short-chain acids | back 96 C. Long-chain fatty acids |
front 97 Bile serves as an excretory route for bilirubin and: A. Glucose | back 97 B. Cholesterol |
front 98 The initial portion of bile is secreted by the: A. Cholangiocytes | back 98 B. Hepatocytes |
front 99 After secretion from hepatocytes, bile first flows in the: A. Canaliculi | back 99 A. Canaliculi |
front 100 Bile in canaliculi flows toward the: A. Portal vein | back 100 B. Interlobular septa |
front 101 Canaliculi empty into terminal bile ducts, which then drain into the hepatic duct and: A. Pancreatic duct | back 101 C. Common bile duct |
front 102 Most gallbladder absorption is driven primarily by active transport of: A. Chloride | back 102 D. Sodium |
front 103 A patient undergoes vagotomy. Which pancreatic stimulus is most directly reduced? A. Secretin | back 103 B. Acetylcholine |
front 104 A meal rich in partially digested protein and long-chain fatty acids enters the small intestine. Which hormone rises most directly? A. CCK | back 104 A. CCK |
front 105 The most abundant solutes secreted in bile are: A. Bile salts | back 105 A. Bile salts |
front 106 Effective gallbladder emptying requires gallbladder contraction plus simultaneous relaxation of the: A. Ileocecal valve | back 106 D. Sphincter of Oddi |
front 107 The most potent stimulus for gallbladder contraction is: A. Secretin | back 107 D. CCK |
front 108 Small quantities of bile salts lost in feces are replaced continuously by the liver in a process referred to here as: A. Biliary diversion | back 108 B. Enterohepatic circulation |
front 109 Brunner’s glands are best described as: A. Compound mucous glands | back 109 A. Compound mucous glands |
front 110 Brunner’s glands are located primarily in the wall of the: A. Distal ileum | back 110 C. First duodenal centimeters |
front 111 Brunner’s glands are inhibited by: A. Parasympathetic activity | back 111 B. Sympathetic stimulation |
front 112 In a highly anxious patient, persistent inhibition of Brunner’s glands would most directly predispose to: A. Jejunal volvulus | back 112 B. Duodenal bulb ulcers |
front 113 Crypts of Lieberkühn in the small intestine are: A. Deep gastric tubules | back 113 C. Small epithelial pits |
front 114 In the small intestine, crypts of Lieberkühn are located over: A. Only proximal duodenum | back 114 D. Entire small-intestinal surface |
front 115 The surfaces of both crypts and villi are covered by epithelium containing goblet cells and: A. Paneth cells | back 115 C. Enterocytes |
front 116 Intestinal goblet cells primarily secrete: A. Pepsinogen | back 116 B. Mucus |
front 117 The main function of goblet-cell secretion in the small intestine is to: A. Acidify luminal contents | back 117 C. Lubricate and protect |
front 118 Enterocytes in the small intestine secrete large quantities of: A. Water | back 118 A. Water |
front 119 Enterocytes also reabsorb water, electrolytes, and: A. Bacterial toxins | back 119 D. Digestive end products |
front 120 Cells deep in the crypts of Lieberkühn continually undergo: A. Meiosis | back 120 C. Mitosis |
front 121 The ongoing cell division in deep crypt cells helps replace the: A. Muscularis externa | back 121 B. Villus epithelium |
front 122 Deep crypt epithelial cells also contribute to formation of new: A. Bile acids | back 122 D. Digestive enzymes |
front 123 The large-intestinal mucosa contains many crypts of Lieberkühn but lacks: A. Goblet cells | back 123 C. Villi |
front 124 Colonic mucus protects the intestinal wall from intense: A. Acid secretion | back 124 B. Bacterial activity |
front 125 The barrier protecting the colonic wall from fecal acids is formed by mucus plus the: A. Osmolarity of chyme | back 125 D. Alkalinity of secretion |
front 126 Mucus and alkaline secretion in the colon prevent fecal acids from: A. Entering the portal vein | back 126 C. Attacking the intestinal wall |
front 127 During bacterial enteritis, an irritated colonic segment secretes extra: A. Water and electrolytes | back 127 A. Water and electrolytes |
front 128 In enteritis, the diarrhea described is beneficial mainly because it: A. Increases bile recycling | back 128 B. Washes away irritants |
front 129 Which finding best identifies large intestine? A. Many villi, no crypts | back 129 C. Crypts without villi |
front 130 A pharmacologist gives a strong CCK antagonist before a fatty meal. Which response is most likely reduced? A. Gallbladder contraction | back 130 A. Gallbladder contraction |