Ch. 23 Digestive System
__________ circulation collects nutrient-rich blood from the GI tract and delivers it to the liver. A. Hepatic portal B. Aortic C. Peritoneal D. Cardiac
A. Hepatic portal
A disorder in which swallowing is hindered or prevented. Botox injections can relax the esophageal sphincter.
Achalasia
Abnormal accumulation of fluid within the peritoneal cavity; if excessive, causes visible bloating of the abdomen. May result from portal hypertension caused by liver cirrhosis or by heart or kidney disease.
Ascites
Which vitamin requires intrinsic factor in order to be absorbed? A. A B. B12 C. C D. K
B. B12
Many of the early food allergies seen in infants are caused by __________. A. lactase deficiency B. absorption of whole proteins C. gallstones D. excessive absorption of fat
B. absorption of whole proteins Absorption of whole proteins, which stimulates an immune response, is the cause of many early-life food allergies.
The digestive system in a cadaver is longer than in a living person because, in a cadaver, there is NO __________. A. enzymatic activity B. muscle tone C. food in the alimentary canal D. digestion taking place
B. muscle tone The digestive system in a cadaver is longer than that in a living person because there is no muscle tone in a cadaver.
Binge-purge behavior—episodes of overeating followed by purging (self-induced vomiting, taking laxatives or diuretics, or excessive exercise). Most common in women of high school or college age. Often associated with stress and depression. Consequences include eroded tooth enamel, stomach trauma or rupture (from vomiting), and severe electrolyte disturbances, which impair heart activity. Therapy includes hospitalization to control behavior, and nutritional counseling.
Bulimia
The permanent dentition consists of __________ teeth in a full set. A. 10 B. 16 C. 20 D. 32
D. 32
Which of the following is the most common cause of peritonitis? A. a perforating ulcer of the stomach B. a ruptured pancreatic cyst C. a perforating abdominal wound D. a burst appendix
D. a burst appendix A burst appendix is the most common cause of peritonitis.
Difficulty swallowing; usually due to obstruction or physical trauma to the esophagus.
Dysphagia
During the intestinal phase of gastric regulation, __________. A. the gastroenteric reflex reduces stomach activity B. secretin causes more HCl release C. hormones reduce chief cell activity D. the enterogastric reflex is turned off E. the stomach is initially stimulated and later inhibited
E. the stomach is initially stimulated and later inhibited right answer feedback:The stomach is initially stimulated and later inhibited.
A disorder in iron metabolism due to excessive/prolonged iron intake or a breakdown of the mucosal iron barrier; excess iron is deposited in the tissues, increasing skin pigmentation and the risk of hepatic cancer and liver cirrhosis. Also called bronze diabetes and iron storage disease.
Hemochromatosis
An inflammation of the parotid glands caused by the mumps virus (myxovirus). A once-common childhood illness now prevented by vaccination with the MMR (measles, mumps, rubella) vaccine. In 25% of mumps cases in adult males, the testes are also infected, which can lead to sterility.
Mumps
Branch of dentistry that prevents and corrects misaligned teeth.
Orthodontics
Term referring to gastric and duodenal ulcers.
Peptic ulcers
Branch of medicine dealing with treatment of diseases of the colon, rectum, and anus.
Proctology
Congenital abnormality in which the pyloric sphincter is abnormally constricted. There is usually no problem until the baby begins to take solid food, and then projectile vomiting begins. Corrected surgically.
Pyloric stenosis
A weak gastroesophageal (cardiac) sphincter can result in heartburn. True False
True
The enteric nervous system is the in-house nerve supply of the alimentary canal. True or False
True
The major means of propulsion through the alimentary canal is peristalsis. True or False
True
Cutting or severing of the vagus nerve to decrease secretion of gastric juice in those with peptic ulcers that do not respond to medication.
Vagotomy
main site of nutrient absorption
mucosa
responsible for segmentation and peristalsis
muscularis externa
protective outermost layer of the alimentary canal
serosa
moderately dense connective tissue that has a rich supply of blood, lymphatic vessels, and nerve fibers
submucosa
You are caring for a patient with late-stage cirrhosis that has led to a decrease in the number of functioning hepatocytes. Which of the following would NOT be typical for a patient with this condition? A. Decreased half-life for drugs processed by the liver. B. Jaundice (yellow discoloration of the skin) C. Inability to digest fats D. Abnormal bleeding
A. Decreased half-life for drugs processed by the liver. Hepatocytes break down and eliminate a variety of drugs. If the number of functional hepatocytes decreases, more of the drug remains in your patient's system, prolonging the half-life and possible reducing the amount of drug to be administered or increasing the dosage interval.
48-Year-Old Female with GallstonesMs. Burton, 48, presents at the clinic complaining of abdominal pain. She is a middle-aged woman, overweight, pale and sweating, with jaundice (yellowish skin and sclerae). Her heart rate is 102 beats/ min and BP is 145/98 mm Hg. She describes the pain as "severe" and "steady" over the past night, accompanied by nausea and vomiting. She sits leaning forward and indicates that the pain is in the epigastric region radiating up to the tip of the right shoulder. Ms. Burton's medical history shows that she has had several episodes of biliary colic (pain caused by gallstones going through the bile duct). She says her current pain is "sort of like that, but it's lasted longer." She says her last meal was a seven-cheese pizza the previous night, and that the pain began 3−4 hours after eating. She denies drinking or smoking. If Ms. Burton's current problem is related to obstruction of the biliary ducts, which other signs or symptoms would you expect her to develop? A. Fatty and gray stools. B. Dizziness and decreased consciousness. C. Low RBC count D. .Blood in her stool.
A. Fatty and gray stools. Because bile cannot pass into the duodenum, fats will not be completely digested, passing out in the stools. Also, the stools will be gray because stercobilin, a breakdown product of bilirubin, will not be present.
Which of the following is NOT a characteristic of the liver? A. It has three lobes. B. It has a role in detoxifying the blood. C. It is highly regenerative. D. It stores glucose as glycogen.
A. It has three lobes.
Which of the following best describes the capillary wall structure found in the liver lobules? A. The capillary walls have openings that allow large proteins and small cells to pass through. B. The capillary walls have openings that allow small proteins to pass through but not cells. C. The capillary walls are continuous, only allowing small molecules and water to pass through. D. The capillary walls only allow water to pass through.
A. The capillary walls have openings that allow large proteins and small cells to pass through. The capillary walls in the lobules of the liver are sinusoidal and allow large proteins and even blood cells to pass, permitting the liver to perform its functions.What is a major function of pancreatic juice?
All of the following are true of swallowing (deglutition) except one. Select the statement that is NOT true of swallowing. A. The epiglottis assists in propelling food into the trachea. B. The mouth, pharynx and esophagus all take part in swallowing C. The involuntary portion of swallowing takes place in the pharynx. D. The voluntary phase of swallowing takes place within the mouth.
A. The epiglottis assists in propelling food into the trachea.
Which of the following is not an important contribution of the bacterial microbiota found in the large intestine? A. digestion of proteins B. suppress the growth of harmful bacteria C. fermentation of carbohydrates D. vitamin synthesis
A. digestion of proteins Digestion of proteins is performed in the stomach and small intestine using enzymes produced by the body, not by gut bacteria.
In order to prevent self-digestion of the pancreas, activation of pancreatic proteases occurs in the __________. A. duodenum B. gallbladder C. liver D. pancreas E. stomach
A. duodenum The pancreatic duct empties into the duodenum, where activation of proteases occurs. Secreting initially inactive forms of proteases prevents self-digestion of the pancreas.
The __________ is the first segment of the small intestine. A. duodenum B. ileum C. jejunum D. colon
A. duodenum This is the first segment of the small intestine.
During deglutition, the bolus passes into the stomach from the esophagus through the __________. A. gastroesophageal sphincter B. esophageal sphincter C. pyloric sphincter D. ileocecal valve E. urethral sphincter
A. gastroesophageal sphincter The gastroesophageal sphincter is the junction between stomach (gastro-) and esophagus. A loose gastroesophageal sphincter can cause heartburn or acid reflux.
Bacterial flora in the large intestine does NOT produce __________. A. intrinsic factor B. vitamin K C. CO2 D. B vitamins
A. intrinsic factor
Emulsification of which organic molecules would be most affected if the liver were severely damaged? A. lipids B. nucleic acids C. proteins D. carbohydrates
A. lipids Fat emulsification occurs by the detergent action of bile salts from the liver.
Which of the following is the major process or function that occurs in the stomach? A. mechanical breakdown B. defecation C. absorption D. deglutition
A. mechanical breakdown Mechanical breakdown occurs in the stomach by churning.
Which layer of the stomach contains the gastric pits that secrete mucus, acid, and digestive enzymes? A. mucosa B. submucosa C. serosa D. muscularis externa
A. mucosa The mucosa of the stomach contains the epithelial lining and the gastric pits, which extend down into the mucosa but do not penetrate the submucosa.
Which of the following conditions is directly associated with an increased risk for heart disease and stroke? A. periodontitis B. dental caries C. impacted wisdom teeth D. gingivitis
A. periodontitis Periodontitis is associated with an increased risk for heart disease or stroke.
Gastric juice does not typically cause a burning sensation within the stomach. But reflux of gastric juice into the esophagus can cause a burning sensation. One reason for the burning sensation caused by the gastric reflux is that the esophagus ______. A. secretes mucus that is not identical to stomach mucus B. is internally lined by epithelial cells that are in direct physical contact with the contents of the esophagushas C. enzymes that react with stomach acid to cause a burning sensation D. None of the listed responses is correct.
A. secretes mucus that is not identical to stomach mucus The function of the mucus-producing esophageal glands is to lubricate the food bolus as it travels toward the stomach.
Where does the process of segmentation occur? A. small intestine B. rectum C. stomach D. esophagus
A. small intestine Several areas of the digestive tract are capable of peristalsis, which propels food onward, but only the small intestine undergoes segmentation. The purpose is to mix food with enzymes and bring it close to intestinal walls.
In a patient suffering from untreated infection-induced peritonitis, an infection in the visceral peritoneum immediately ______. A. spreads directly to the parietal peritoneum B. spreads directly to the retroperitoneal organs C. causes appendicitis D. All of the listed responses are correct.
A. spreads directly to the parietal peritoneum The parietal peritoneum lines the body wall and is separated from the visceral peritoneum by the fluid-filled peritoneal space.
Which of the following products does the stomach produce? A. mucus and amylase B. HCl and intrinsic factor C. bile and trypsin D. pepsinogen and secretin
B. HCl and intrinsic factor HCl, IF, mucus, and pepsinogen (pepsin) are products of the stomach.
Which of the following is the best illustration of the difference between metabolism and digestion? A. Digestion has a wide variety of chemical reactions while metabolism is restricted to only a few reaction types B. Metabolism comprises all of the chemical reactions preformed within the body while digestion is only the breakdown of food within the GI tract C. .Digestions must happen first for metabolism to follow it. D. Digestion requires enzymes for it to take place while metabolism does not necessarily need or use them.
B. Metabolism comprises all of the chemical reactions preformed within the body while digestion is only the breakdown of food within the GI tract
48-Year-Old Female with GallstonesMs. Burton, 48, presents at the clinic complaining of abdominal pain. She is a middle-aged woman, overweight, pale and sweating, with jaundice (yellowish skin and sclerae). Her heart rate is 102 beats/ min and BP is 145/98 mm Hg. She describes the pain as "severe" and "steady" over the past night, accompanied by nausea and vomiting. She sits leaning forward and indicates that the pain is in the epigastric region radiating up to the tip of the right shoulder. Ms. Burton's medical history shows that she has had several episodes of biliary colic (pain caused by gallstones going through the bile duct). She says her current pain is "sort of like that, but it's lasted longer." She says her last meal was a seven-cheese pizza the previous night, and that the pain began 3−4 hours after eating. She denies drinking or smoking. Which of the following correctly interprets these results? A. The presence of pancreatic enzymes in the blood is good news because it indicates that the pancreas is still functioning. B. The location of the gallstone is a problem because it blocks bile from entering the duodenum and forces bile up into the pancreas. C. The dilation of the ducts is good news because that will make it easier for gallstones to pass. D. The location of the gallstone is good news because it shows that the stone has almost passed into the duodenum.
B. The location of the gallstone is a problem because it blocks bile from entering the duodenum and forces bile up into the pancreas.
What is the benefit of having tonsils at the oral entry to the pharynx? A. The tonsils secrete amylase to begin digestion of carbohydrates in the oral cavity. B. The tonsils gather and remove many of the pathogens entering the pharynx in food or liquid. C. Tonsils secrete an alkaline mucus that protects the esophagus from acid reflux. D. Tonsils secrete intrinsic factor, which is required for absorption of vitamin B12 in the stomach.
B. The tonsils gather and remove many of the pathogens entering the pharynx in food or liquid. The circle of tonsils around the opening of the pharynx is protective because air, food, and liquids, none of which is typically sterile, pass the tonsils almost immediately. This is beneficial because the lymphocytes and macrophages associated with the tonsils are exposed to microbes, allowing for immune system learning, while also attacking microbes that come in with these substances.
Some aspects of the __________ phase of gastric secretion, which occur before food enters the stomach, may be considered conditioned reflexes. A. esophageal B. cephalic C. intestinal D. gastric
B. cephalic Some aspects of the cephalic phase of gastric secretion, which is stimulated by the sight, taste, aroma, or thought of food, may be considered conditioned reflexes.
The phases of gastric secretion, from first to last, are __________. A. cephalic phase, intestinal phase, gastric phase B. cephalic phase, gastric phase, intestinal phase C. intestinal phase, gastric phase, cephalic phase D. gastric phase, cephalic phase, intestinal phase
B. cephalic phase, gastric phase, intestinal phase
Which of the following cells produce pepsinogen? A. G cells B. chief cells C. mucous cells D. parietal cells E. enteroendocrine cells
B. chief cells Pepsinogen is the inactive form of pepsin, which is produced by chief cells located in the basal region of gastric glands.
What structural modification of the small intestine slows the movement of chyme through the lumen? A. intestinal crypts B. circular folds C. microvilli D. villi
B. circular folds The circular folds of the small intestine help slow the progress of food through the intestine so that it can be digested and absorbed more effectively. These folds also increase surface area and help mix chyme.
Halitosis is caused by __________. A. loss of teeth B. increased anaerobic bacterial activity at the back of the tongue C. lack of amylase in saliva D. increased salivation
B. increased anaerobic bacterial activity at the back of the tongue right answer feedback:Halitosis is caused by increased anaerobic bacterial activity at the back of the tongue.
Which of the following is NOT an accessory organ of the digestive system? A. salivary glands B. intestines C. tongue D. teeth
B. intestines The intestines are part of the alimentary canal; they are not an accessory organ.
Which of the following is a condition affecting the large intestine that is NOT explained by anatomical or biochemical abnormalities? A. pernicious anemia B. irritable bowel syndrome C. a hiatal hernia D. celiac disease
B. irritable bowel syndrome Irritable bowel syndrome is not explained by anatomical or biochemical abnormalities and stress management is an important aspect of treatment.
The ________ contains lobules with sinusoids (lined with macrophages) that lead to a central venous structure. A. stomach B. liver C. spleen D. pancreas
B. liver
Digestion of carbohydrates and proteins by brush border enzymes occurs within the __________ of the small intestine. A. goblet cells B. microvilli C. circular folds D. villi
B. microvilli
Which sequence below represents the correct order of the tunics of the GI tract, starting from the layer adjacent to the lumen and moving superficially? A. submucosa, mucosa, muscularis externa, serosa B. mucosa, submucosa, muscularis externa, serosa C. serosa, mucosa, muscularis externa, submucosa D. mucosa, muscularis externa, submucosa, serosa E. muscularis externa, serosa, submucosa, mucosa
B. mucosa, submucosa, muscularis externa, serosa The mucosa is the layer that lines the lumen; it is followed by the submucosa, muscularis externa, and serosa.
The myenteric nerve plexus is located in which tunic of the alimentary canal? A. submucosa B. muscularis externa C. serosa D. mucosa
B. muscularis externa The myenteric nerve plexus lies between the circular and longitudinal muscle layers of the GI tract wall and controls motility.
Which area of the stomach directly adjoins the small intestine? A. fundus B. pylorus C. body D. cardia
B. pylorus The pylorus is the lowest part of the stomach. It attaches to and empties food into the small intestine via the pyloric sphincter.
Most water is absorbed in the __________. A. stomach B. small intestine C. liver D. large intestine
B. small intestine
The major site for nutrient absorption is the __________. A. large intestine B. small intestine C. stomach D. mouth
B. small intestine
Which layer of the alimentary canal contains not only glands and blood vessels but also a nerve plexus that helps regulate digestive activity? A. serosa B. submucosa C. mucosa D. muscularis externa
B. submucosa The submucosa layer contains blood and lymphatic vessels, lymphoid follicles, and the submucosal plexus of nerve fibers.
The __________ is the serous membrane that covers most digestive organs. A. parietal peritoneum B. visceral peritoneum C. omenta D. mesentery
B. visceral peritoneum The visceral peritoneum covers the external surfaces of most digestive organs and is continuous with the parietal peritoneum that lines the body wall.
A pathological change in the epithelium of the lower esophagus from stratified squamous to a columnar epithelium. A possible sequel to untreated chronic gastroesophageal reflux due to hiatal hernia, it predisposes the individual to aggressive esophageal cancer (adenocarcinoma).
Barrett's esophagus
Grinding or clenching of teeth, usually at night during sleep in response to stress. Can wear down and crack the teeth.
Bruxism
Your patient has had a total gastrectomy (removal of the stomach). Which of these potential problems are you MOST concerned about? A. Inability to tolerate fats because of absent bile salts B. Excessive bleeding as a result of absent clotting factors in the blood. C. Anemia D. Inability to digest starch because of the absence of amylase
C. Anemia The parietal cells of the stomach produce intrinsic factor, which permits the absorption of vitamin B12, a nutrient required for the maturation of red blood cells. Unless your patient receives vitamin B12 replacement therapy, he or she will develop pernicious anemia.
__________ is/are NOT found in pancreatic secretions. A. Bicarbonate ions B. Chymotrypsinogen C. Cholecystokinin (CCK) D. Procarboxypeptidase
C. Cholecystokinin (CCK)
Which of the following statements about the mesentery is INCORRECT? A. It provides a route for blood vessels, lymphatics, and nerves to reach the digestive viscera. B. Omenta is the special name for part of the mesentery extending from the curvatures of the stomach. C. It is composed of a layer of serous membrane fused with a layer of mucous membrane. D. It holds the organs of the abdomen in place.
C. It is composed of a layer of serous membrane fused with a layer of mucous membrane. The mesentery is composed of two layers of serous membranes fused together.
What intestinal structure(s) consist(s) of protective aggregated nodules of lymphocytes and macrophages? A. the intestinal crypts B. the gastric pits C. Peyer's patches D. the muscularis externa E. the muscularis mucosae
C. Peyer's patches Peyer's patches, which contain lymphocytes and macrophages, increase in number toward the end of the ileum, indicating that this region is rife with bacteria that must be prevented from entering the bloodstream.
Which of the following is NOT a function of saliva? A. Saliva dissolves food chemicals so that they can be tasted B. .Saliva cleanses the mouth. C. Saliva contains enzymes that begin the chemical breakdown of proteins. D. Saliva moistens food and helps compact it into a bolus.
C. Saliva contains enzymes that begin the chemical breakdown of proteins.
Which of the following does NOT correctly describe basic regulation of digestive activity? A. pH, stretch, and osmolarity are some of the stimuli that can trigger digestive reflexes. B. Short reflexes act locally in the GI tract. C. The enteric nervous system is under conscious control. D. Digestive system effectors are smooth muscle and glands.
C. The enteric nervous system is under conscious control. Neural control over the digestive system is through the autonomic nervous system, which does not function under conscious control mechanisms.
Which of the following is the best explanation of the benefit in the digestive system having the largest collection of lymphoid tissue (MALT) at the distal end of the small intestine? A. The body will actively excrete pathogens out of the body, into the digestive system, to be removed from the body in feces. B. The alkaline secretions of the small intestine aid in the growth of bacteria and these bacteria must be controlled. C. The huge numbers of bacteria living in the large intestine must be prevented from entering the lumen of the small intestine so they do not absorb the nutrients before the host can. D. The digestive systems first and foremost job is to digest and absorb nutrients so it puts off immunity for last.
C. The huge numbers of bacteria living in the large intestine must be prevented from entering the lumen of the small intestine so they do not absorb the nutrients before the host can.
Which enzyme(s) is/are responsible for the chemical breakdown of carbohydrates? A. trypsin B. proteases C. amylases D. nuclease
C. amylases Amylases hydrolyze carbohydrate chains.
What substances from different organs would mix together at the hepatopancreatic ampulla? A. brush border enzymes and intrinsic factor B. secretin and CCK C. bile and pancreatic enzymes D. HCl and pepsin
C. bile and pancreatic enzymes Bile and pancreatic enzymes mix at the hepatopancreatic ampulla.
When the diet lacks fiber and the volume of residues in the colon is small, the colon narrows and its contractions become more powerful, increasing the pressure on its walls. This promotes formation of __________. A. irritable bowel syndrome (IBS) B. gallstones C. diverticula D. cystic fibrosis
C. diverticula When the diet lacks fiber and the volume of residues in the colon is small, the colon narrows and its contractions become more powerful, increasing the pressure on its walls. This promotes formation of diverticula, small herniations of the mucosa through the colon walls. This condition, called diverticulosis, most commonly occurs in the sigmoid colon, and affects over half of people over age 70. In 4-10% of cases, diverticulosis progresses to diverticulitis, in which the diverticula become inflamed and may rupture, leaking into the peritoneal cavity, which can be life-threatening.
A doctor consulting a patient that recently has had their gall bladder removed would likely advise ________. A. eating fewer, but larger meals B. eating a low to no carb diet C. eating foods that are low in fat C. increasing unsaturated fats while eliminating trans fats in their diets
C. eating foods that are low in fat
Which teeth in the permanent dentition are best suited for cutting or nipping off pieces of food? A. canines B. premolars (bicuspids) C. incisors D. molars
C. incisors The location and shape of the incisors make them ideally suited for cutting and nipping food.
What is a major function of pancreatic juice? A. emulsifying fats by breaking them into smaller pieces B. secreting hormones that help digest food in the duodenum C. neutralizing chyme entering the small intestine from the stomach D. acidifying the contents of the small intestine
C. neutralizing chyme entering the small intestine from the stomach Pancreatic juice contains bicarbonate (as baking soda does) that can neutralize the pH of acidic chyme coming from the stomach.
What are the main organic molecules digested in the stomach? nucleic acids A. salts B. lipids C. proteins D. carbohydrates
C. proteins :The main enzyme produced by the stomach is pepsin, which digests protein (gastric lipases are only of minor importance).
From the esophagus to the anus, the walls of the alimentary canal have the same four basic tunics. The __________ is the outermost layer of the walls of the intraperitoneal organs. A. muscularis B. mucosa C. serosa D. submucosa
C. serosa The visceral peritoneum, or serosa, forms the outermost layer (tunic) along most of the alimentary canal. In the esophagus, which is located in the thoracic instead of the abdominopelvic cavity, the serosa is replaced by an adventitia (dense connective tissue). Retroperitoneal organs have both an adventitia (on the side facing the dorsal body wall) and a serosa (on the side facing the peritoneal cavity).
The increased concentration of HCO3- in blood draining from the stomach is called __________. A. the chloride shift B. the enterogastric reflex C. the alkaline tide D. the gastric phase
C. the alkaline tide
Which of the following teeth are most commonly impacted? A. incisors B. deciduous teeth C. wisdom teeth D. premolars
C. wisdom teeth Wisdom teeth are the most common teeth to become impacted.
The human GI tract is home to a complex ecosystem of microbial cells, which comprise the gut microbiota. Which of the following is true of the microbiota? A. Generally, the highest concentration of GI tract microbes is found in the colon. B. Metabolism by the gut microbiota results in small amounts of vitamins and short-chain fatty acids which can be absorbed and utilized by cells of the body. C. Normally, beneficial bacteria vastly outnumber harmful bacteria in the microbiota. D. All of the above.
D. All of the above. Review information about the bacterial microbiota in your textbook.
__________ can result if food passes too slowly through the large intestine. A. Colitis B. Diarrhea C. Irritable bowel syndrome D. Constipation
D. Constipation When food remains in the colon for extended periods, too much water is absorbed and the stool becomes hard and difficult to pass. This condition, called constipation, may result from insufficient fiber or fluid in the diet, improper bowel habits (failing to heed the "call"), lack of exercise, or laxative abuse.
Which of the following is a characteristic of the large intestine? A. It has villi. B. It is longer than the small intestine. C. It is the site for acid neutralization. D. It contains epiploic appendages. E. It provides no absorptive function.
D. It contains epiploic appendages. Suspended from the large intestine are epiploic appendages, which are small fat-filled pouches of visceral peritoneum.
Which of the following is NOT a function of the stomach? A. absorption of a few fat-soluble substances B. temporary holding area for food until it can be moved to the duodenum C. mechanical breakdown of the bolus into chyme D. chemical digestion of carbohydrates
D. chemical digestion of carbohydrates
What would be the effect of stripping the small intestines of their villi A. The large intestine would take over as the primary absorptive site. B. A duodenal ulcer would develop. C. Salivary amylase secretion would increase. D. decreased surface area for absorption
D. decreased surface area for absorption right answer feedback:Decreased intestinal surface area would lead to decreased absorption, leading to a long list of problems such as malnutrition, dehydration, diarrhea, and electrolyte imbalance.
The __________ is the first segment of the small intestine. A. colon B. ileum C. jejunum D. duodenum
D. duodenum
Bile is stored and concentrated in the __________. A. liver B. stomach C. pancreas D. gallbladder
D. gallbladder
The __________ circulation collects nutrient-rich venous blood draining from the digestive viscera. A. splanchnic B. pulmonary C. enterohepatic D. hepatic portal
D. hepatic portal The hepatic portal circulation drains all of the blood from the digestive organs and routes that blood through the liver for processing.
Most absorption of nutrients occurs in the __________. A. stomach and duodenum B. descending and sigmoid colon C. cecum and ascending colon D. jejunum and ileum
D. jejunum and ileum The majority of nutrients are absorbed as digesting foods make their way through the jejunum (~8 feet long) and ileum (~12 feet long) of the small intestine. Although absorption begins in the duodenum, it is too short (~12 inches long) to account for the majority of nutrient absorption.
The final product of carbohydrate digestion is __________. A. glycogen B. polysaccharides C. starch D. monosaccharides E. disaccharides
D. monosaccharides With the exception of fatty acids, all macromolecules are broken down to their monomers, such as when enzymes hydrolyze complex carbohydrates into monosaccharides.
Which of the following is NOT an effect of aging on digestive system activity? A. fewer digestive juices are produced B. less efficient absorptions C. lowing of peristalsis D. more frequent bowel movements
D. more frequent bowel movements During old age, GI tract activity declines. This results in less frequent (not more frequent) bowel movements. In addition, fewer digestive juices are produced, absorption is less efficient, and peristalsis slows. Return to Assignment
The myxovirus causes __________. A. irritable bowel syndrome B. measles C. infectious mononucleosis D. mumps
D. mumps The myxovirus causes mumps.
Pepsin enzymatically digests __________. A. fat B. carbohydrate C. nucleic acids D. protein
D. protein
Which organ of the digestive tract is the body's major digestive organ? A. stomach B. liver C. large intestine D. small intestine
D. small intestine The small intestine is the major digestive organ because it is the site of the majority of enzymatic digestion and absorption of nutrients.
Which of the following is a function of the gallbladder? A. secreting pancreatic juice B. metabolizing carbohydrate C. converting pepsinogen to pepsin D. storing and concentrating bile
D. storing and concentrating bile Bile that is not immediately needed for digestion is concentrated and stored by the gallbladder.
Which of the following is NOT a function of the large intestine? A. absorption of water B. absorption of electrolytes C. synthesis of vitamins D. synthesis of intrinsic factor
D. synthesis of intrinsic factor Intrinsic factor is produced in the stomach; it is required for absorption of vitamin B12 in the small intestine.
The short reflexes in the digestive system are stimulated by __________. A. the sympathetic division of the autonomic nervous system B. the parasympathetic division of the autonomic nervous system C. higher brain centers D. the enteric nerve plexuses
D. the enteric nerve plexuses The enteric nerve plexuses stimulate the short reflexes in the digestive system.
The only stomach function that is essential to life is __________. A. the presence of HCl B. the secretion of pepsinogen C. mechanical digestion D. the secretion of intrinsic factor
D. the secretion of intrinsic factor The secretion of intrinsic factor is the only stomach function that is essential to life.
The serous membrane that covers the external surfaces of most digestive organs is called the __________. A. mesentery B. parietal peritoneum C. omentum D. visceral peritoneum
D. visceral peritoneum
Which regulatory chemical stimulates gastric gland activity and motility? A. secretin B. histamine C. vasoactive peptide D. CCK E. gastrin
E. gastrin Gastrin is the major stomach hormone. Both the stomach and the small intestine produce this chemical.
Which of the following cells produce HCl? A. chief cells B. mucous cells C. G cells D. enteroendocrine cells E. parietal cells
E. parietal cells Parietal cells make HCl and intrinsic factor
The main propulsive force that occurs in the majority of the alimentary canal is called __________. A. ingestion B. segmentation C. swallowing D. defecation E. peristalsis
E. peristalsis Peristalsis occurs as alternating waves of contraction and relaxation and serves to propel food down the tract.
Visual examination of a ventral body cavity or the interior of a visceral organ with a flexible tubelike device called an endoscope, which contains a light source and a lens. A general term for a colonoscopy (viewing the colon), sigmoidoscopy (viewing the sigmoid colon), etc.
Endoscopy
Inflammation of the intestine, especially the small intestine.
Enteritis
Saliva contains enzymes that break down proteins. True False
False
A condition in which all GI tract movement stops and the gut appears to be paralyzed. Can result from electrolyte imbalances and blockade of parasympathetic impulses by drugs (such as those commonly used during abdominal surgery); usually reversed when these interferences end. The reappearance of intestinal sounds (gurgling, etc.) indicates restoration of motility.
Ileus
A noncontagious, periodic inflammation of the intestinal wall now understood to be an abnormal immune and inflammatory response to bacterial antigens that normally occur in the intestine. Linked to TH17 cells, certain cytokines, and the loss of a normal epithelial barrier. Afflicts up to two of every 1000 people. Symptoms include cramping, diarrhea, weight loss, and intestinal bleeding. Two subtypes occur: (1) Crohn's disease is a syndrome characterized by relapsing and remitting periods. Deep ulcers and fissures can develop anywhere along the GI tract, but mostly occur in the terminal ileum. (2) Ulcerative colitis is characterized by inflammation of the large-intestinal mucosa, mainly in the rectum. Both types are treated with anti-inflammatory and immunosuppressant drugs and sometimes probiotic agents and antibiotics. Extremely severe cases of ulcerative colitis are treated by colectomy (removal of a portion of the colon).
Inflammatory bowel disease (IBD)
Examination of the peritoneal cavity and its organs with an endoscope inserted through the anterior abdominal wall. Often used to assess the condition of the digestive organs and the pelvic reproductive organs of females.
Laparoscopy
A rare but extremely serious inflammation of the pancreas. May result from excessively high levels of fat in the blood or excessive alcohol ingestion, but most acute cases arise from gallstones that block the bile duct. Pancreatic enzymes are activated in the pancreatic duct, causing the pancreatic tissue and duct to be digested (literally, eaten from within). This painful condition can lead to nutritional deficiencies because pancreatic enzymes are essential to food digestion in the small intestine.
Pancreatitis
Diarrhea results when food passes too quickly through the large intestine. True False
True
Most digestion occurs in the small intestine. True False
True
Someone on a fat-free diet would NOT efficiently absorb vitamin D from the diet. True False
True
monosaccharides
carbohydrates
nucleotides
lipids
nucleotides
nucleic acids
amino acids
proteins
