Seeley's Anatomy & Physiology Ch 24 - Digestive System

*16) True or False? The enteric nervous system acts independently of the CNS to control local reflexes in the digestive tract. TRUE FALSE

TRUE

When and where are various ions absorbed?

The majority of the ions are absorbed in the duodenum and jejunum of the small intestine.

Describe the mechanism of absorption

The mechanism by which absorption occurs depends on the type of molecule involved. Molecules pass out of the digestive tract by simple diffusion, facilitated diffusion, active transport, or cotransport

Describe the enzymatic digestion of lipids

-Lipase digests lipid molecules. The vast majority of lipase is secreted by the pancreas and is referred to as pancreatic lipase. -A minor amount of lingual lipase, which is secreted in the oral cavity and swallowed with food, digests a small amount (<10%) of lipid in the stomach. -The stomach also produces very small amounts of gastric lipase. The primary products of lipase digestion are free fatty acids and monoglycerides.

Describe the enzymatic digestion of proteins

-Pepsin secreted by the stomach catalyzes the cleavage of covalent bonds in proteins to produce smaller polypeptide chains. -Gastric pepsin digests as much as 10-20% of the total ingested protein. -Proteolytic enzymes produced in the pancreas continue the digestive process and produce small peptide chains. These are broken down into tripeptides, dipeptides, and amino acids by peptidases bound to the microvilli of the small intestine. Each peptidase is specific for a certain peptide chain length or for a certain amino acid sequence.

*51) Gastritis, peptic ulcers, and gastric cancer can all be caused by A) Helicobacter pylori, a bacterium. B) increased secretion of gastric bicarbonate. C) pH of the stomach contents continuously greater than 4. D) increased mucus production by the neck cells. E) None of the choices are correct.

A) Helicobacter pylori, a bacterium.

17) Which disease is caused by the absence of enteric neurons in the distal large intestine? A) Hirschsprung disease B) Multiple endocrine neoplasia type 2 C) Spastic colon D) Gastroenteritis

A) Hirschsprung disease

*7) Which digestive activity is NOT correctly matched to its location? A) Killing microorganisms with lysozyme - stomach B) Digestion of carbohydrates - mouth C) Absorption of nutrients - small intestine D) Production of mucus - esophagus

A) Killing microorganisms with lysozyme - stomach

*74) Which of the following lipoproteins contains the highest percentage of cholesterol? A) LDL B) HDL C) VLDL D) Chylomicron E) CDL

A) LDL

43) Anticipation of eating food causes an increase in secretion of gastric juice. This phase of gastric secretion is called the ________ phase. A) cephalic B) gastric C) intestinal D) pancreatic E) conscious

A) cephalic

*48) The enterogastric reflex can be triggered by A) distention of the duodenal wall. B) the presence of food in the stomach. C) increased pH in the duodenum. D) the cerebral cortex. E) the hormone secretin.

A) distention of the duodenal wall.

29) Salivary gland secretion is primarily controlled by the A) facial and glossopharyngeal nerves. B) vagus nerve. C) taste centers of the medulla. D) intercostal nerves. E) trigeminal nerve

A) facial and glossopharyngeal nerves.

76) A cell needs a receptor in order to absorb LDLs. A disease that interferes with the functioning of these LDL receptors would A) increase serum cholesterol levels. B) decrease serum cholesterol levels. C) halt endocytosis. D) promote endocytosis. E) have no effect on serum cholesterol or endocytosis.

A) increase serum cholesterol levels.

45) The intestinal phase of gastric secretion A) is controlled by the entrance of acidic chyme into the duodenum. B) leads to increased gastric secretion if duodenal pH falls below 2. C) only stimulates gastric secretion. D) will decrease gastric secretion when gastrin is released by the duodenum. E) is controlled by the entrance of alkaline material into the small intestines.

A) is controlled by the entrance of acidic chyme into the duodenum.

*72) The defecation reflex A) is stimulated by distention of the rectum. B) inhibits further peristalsis in the rectum and lower colon. C) constricts the internal anal sphincter. D) lasts several hours. E) None of the choices are correct.

A) is stimulated by distention of the rectum.

28) The salivary glands located just anterior to the ear are the ________ glands. A) parotid B) submandibular C) buccal D) labial E) sublingual

A) parotid

*39) Reflux of gastric contents into the esophagus occurs because of A) relaxation of the cardiac sphincter. B) contraction of the pyloric sphincter. C) spasms of the submucosal layer of the stomach wall. D) increased hydrochloric acid production by the parietal cells. E) increased amounts of mucus produced by the stomach.

A) relaxation of the cardiac sphincter.

*19) The role of acetylcholine in the digestive tract is to ________, while the role of norepinephrine is to ________. A) stimulate; stimulate B) stimulate; inhibit C) inhibit; inhibit

A) stimulate; stimulate

3) Which is the correct order of the regions of the digestive tract from superior to inferior? A) Pharynx, esophagus, large intestine, small intestine B) Oral cavity, stomach, small intestine, large intestine C) Stomach, esophagus, large intestine, small intestine D) Anus, large intestine, stomach, esophagus

B) Oral cavity, stomach, small intestine, large intestine

*36) Which of the following cell types of the stomach is correctly matched with its function? (could be matching) A) Mucous cells - produce intrinsic factor B) Parietal cells - produce hydrochloric acid C) Chief cells - produce mucus D) Endocrine cells - produce enzymes E) Chief cells - produce hormones

B) Parietal cells - produce hydrochloric acid

*77) Which of the following enzymes digests protein? A) Bile B) Pepsin C) Isomaltose D) Sucrase E) Lipase

B) Pepsin

40) Which of the following are secreted by the stomach? A) Amylase and lipase B) Pepsinogen and intrinsic factor C) Bile and lipase D) Trypsin and amylase E) Bicarbonate and secretin

B) Pepsinogen and intrinsic factor

34) What moves the bolus during the esophageal phase of deglutition? A) Pharyngeal constriction B) Peristalsis C) The tongue D) Segmentation

B) Peristalsis

*37) Which of the following regions of the stomach is correctly matched with its description? A) Body - portion closest to the esophagus B) Pylorus - the most inferior portion of the stomach C) Fundus - opening from the stomach into the duodenum D) Cardiac region - the largest portion of the stomach E) Pyloric opening - opening from the esophagus

B) Pylorus - the most inferior portion of the stomach

20) What is the role of serotonin in the digestive tract? A) Decrease nausea B) Stimulate motility C) Hormone release D) Inhibit motility

B) Stimulate motility

31) How does the muscularis layer of the esophagus differ from the rest of the digestive tract? A) It is all skeletal muscle. B) The superior part is skeletal muscle. C) The inferior part is skeletal muscle. D) It has alternating smooth and skeletal muscle sections.

B) The superior part is skeletal muscle.

*8) Diffusion and active transport are likely to be important in A) mastication of food. B) absorption of food. C) elimination of undigested food. D) propulsion of food through the digestive tract. E) mixing of food.

B) absorption of food

*49) Food in the stomach is squeezed and mixed with gastric juices, forming a semiliquid called ________. A) bolusin B) chyme C) bile D) phlegm

B) chyme

44) The distention of the stomach by food is the primary stimulus to begin the ________ phase of gastric secretion. A) cephalic B) gastric C) intestinal D) cystic E) hepatic

B) gastric

57) Nutrient-rich blood from the digestive tract comes to the liver by way of the ________. A) hepatic artery B) hepatic portal vein C) hepatic vein D) inferior vena cava E) celiac trunk

B) hepatic portal vein

59) Damage to the liver would hamper digestion of ________. A) carbohydrates B) lipids C) proteins D) disaccharides E) All of the choices are correct.

B) lipids

58) Bile is produced by cells of the ________. A) duodenum B) liver C) gallbladder D) pancreas E) hepatopancreatic ampulla

B) liver

23) The lips, cheek, and tongue all aid in ________. A) speech and swallowing B) mastication, speech, and swallowing C) mastication and swallowing D) mastication and sense of taste E) deglutition and peristalsis

B) mastication, speech, and swallowing

*60) The liver A) produces secretions that help neutralize stomach acids and emulsify fats. B) produces several digestive enzymes. C) stores vitamin C. D) receives oxygenated blood from the portal vein. E) cannot synthesize new molecules.

B) produces several digestive enzymes.

5) The movement of food through the digestive is ________. A) segmentation B) propulsion C) mixing D) mastication

B) propulsion

68) When chyme enters the duodenum, ________ is released and stimulates the pancreas to secrete bicarbonates. A) gastrin B) secretin C) insulin D) cholecystokinin E) glucagon

B) secretin

Identify the part of the stomach labeled: E

Body

46) Which of the following would inhibit both gastric secretion and gastric motility? A) Vagal stimulation B) Chewing and swallowing food C) Cholecystokinin (CCK) D) Gastrin E) Large amounts of fiber in the diet

C) Cholecystokinin (CCK)

*4) Which of the following is a function of the digestive system? A) Cellular respiration B) Food selection C) Elimination of undigested food D) Regulation of blood pH E) Integration and coordination of other systems

C) Elimination of undigested food

*30) Which structure moves food from the pharynx to the stomach? A) Larynx B) Laryngopharynx C) Esophagus D) Epiglottis

C) Esophagus

47) Which of the following would stimulate gastric secretion? A) Acidic chyme in duodenum B) Secretin C) Gastrin D) Cholecystokinin E) Pepsin

C) Gastrin

1) Which of the following is an accessory organ of the digestive tract? A) Pharynx B) Stomach C) Liver D) Large intestine

C) Liver

*13) What is the function of interstitial cells of the myenteric plexus? A) Chemoreceptors that detect the chemical composition of food B) Production of mucus for lubrication and protection C) Pacemaker cells that promote rhythmic contractions of the smooth muscle D) Release of enzymes for chemical digestion

C) Pacemaker cells that promote rhythmic contractions of the smooth muscle

*32) Why does the superior part of the esophagus contain skeletal muscle instead of smooth muscle? A) The first phase of swallowing is under involuntary control. B) The second phase of swallowing is under voluntary control. C) The first phase of swallowing is under voluntary control. D) The second phase of swallowing is under involuntary control.

C) The first phase of swallowing is under voluntary control.

*56) Which of the following statements regarding the pancreas is true? A) The head of the pancreas lies in the curvature of the ileum. B) The pancreatic duct carries both enzymes and hormones. C) The pancreatic acinar cells secrete digestive enzymes. D) The pancreas assists the stomach in the absorption of digested food. E) The pancreas digests sugar.

C) The pancreatic acinar cells secrete digestive enzymes.

70) Which of the following enzymes is mismatched with its substrate? A) Pepsin - protein B) Amylase - starch C) Trypsin - nucleic acids D) Lipase - fat E) Deoxyribonucleases - DNA

C) Trypsin - nucleic acids

33) Which of the following is the correct order for the phases of deglutition? A) Pharyngeal, voluntary, esophageal B) Esophageal, pharyngeal, voluntary C) Voluntary, pharyngeal, esophageal D) Voluntary, esophageal, pharyngeal

C) Voluntary, pharyngeal, esophageal

24) Lipid-soluble drugs placed under the tongue A) are more easily swallowed. B) can be detected by taste buds. C) are quickly dissolved and absorbed. D) are then easy to chew. E) are not readily absorbed.

C) are quickly dissolved and absorbed.

*53) The hepatopancreatic ampulla is formed by the union of the A) pancreatic duct with the lacteals. B) greater duodenal papilla with the lesser duodenal papilla. C) common bile duct and pancreatic duct. D) cystic duct and interlobular duct. E) hepatic ducts and cystic ducts.

C) common bile duct and pancreatic duct.

*41) Intrinsic factor A) increases gastric motility. B) causes the release of stomach acid. C) facilitates the absorption of vitamin B12. D) protects the stomach lining from the effects of stomach acid. E) stimulates the synthesis of DNA.

C) facilitates the absorption of vitamin B12.

50) Duodenal gland secretion prevents A) digestive enzyme release. B) release of bile from the liver. C) irritation of the duodenal mucosa by acidic chyme and digestive enzymes. D) the release of insulin. E) peristalsis.

C) irritation of the duodenal mucosa by acidic chyme and digestive enzymes.

65) The major secretion of the large intestine is ________. A) bile B) hormones C) mucus D) vitamins E) bacteria

C) mucus

75) LDLs are taken into a cell by the process of ________. A) simple diffusion B) osmosis C) receptor mediated endocytosis D) HDL carrier molecules E) facilitated diffusion

C) receptor mediated endocytosis

55) The gallbladder ________. A) produces bile B) is attached to the pancreas C) stores bile D) produces secretin E) breaks down red blood cells

C) stores bile

27) The salivary glands that open into the oral cavity beside the frenulum of the tongue are the ________ glands. A) parotid B) sublingual C) submandibular D) labial E) lacrimal

C) submandibular

*15) Parasympathetic nerves extend to the digestive tract through the ________ nerve. A) gastric B) cardiac C) vagus D) accessory

C) vagus

Describe the movement of water through the intestinal wall

Controlled by osmotic pressure. Water moves out of the small intestine and into the colon of the large intestine.

63) Which of the following is NOT part of a portal triad? A) Hepatic artery B) Hepatic duct C) Hepatic portal vein D) Central vein

D) Central vein

22) Which of the following attaches the liver to the anterior abdominal wall? A) Greater omentum B) Lesser omentum C) Transverse mesocolon D) Falciform ligament E) Round ligament

D) Falciform ligament

18) What are the two major neurotransmitters of the enteric nervous system? A) Epinephrine and serotonin B) Epinephrine and norepinephrine C) Acetylcholine and epinephrine D) Norepinephrine and acetylcholine

D) Norepinephrine and acetylcholine

64) Which of the following is located closest to the rectum? A) Ascending colon B) Descending colon C) Transverse colon D) Sigmoid colon E) Cecum

D) Sigmoid colon

6) The movement of molecules out of the digestive tract into circulation or the lymphatic system is ________. A) secretion B) peristalsis C) chemical digestion D) absorption

D) absorption

9) The muscularis layer in the wall of the digestive tract is A) skeletal muscle throughout the tract, especially in the large intestine. B) the layer of the digestive tract wall that contains capillaries. C) in direct contact with the food that is consumed. D) composed of a layer of circular smooth muscle fibers and a layer of longitudinal smooth muscle fibers. E) connective tissue and the peritoneum.

D) composed of a layer of circular smooth muscle fibers and a layer of longitudinal smooth muscle fibers.

*10) The enteric plexus A) is found in the mucosa. B) consists of the myenteric plexus and the celiac plexus. C) contains sympathetic neurons and fibers. D) controls movement and secretion of the digestive tract. E) is a valve in the GI tract.

D) controls movement and secretion of the digestive tract.

71) One of the major functions of the large intestine is to A) produce vitamin C. B) regulate the release of bile. C) break down hemoglobin to release bilirubin. D) convert chyme to feces.

D) convert chyme to feces.

*38) Inflammation of the stomach mucosa in the area superior to the pyloric sphincter is most appropriately referred to as ________. A) esophagitis B) a duodenal ulcer C) a hiatal hernia D) gastric ulcer E) indigestion

D) gastric ulcer

35) The esophagus A) extends from the fauces to the stomach. B) has cartilage in its walls to keep it from collapsing. C) produces two enzymes that digest proteins. D) has upper and lower sphincters to regulate movement of food. E) has thin walls of connective tissue.

D) has upper and lower sphincters to regulate movement of food.

52) The villi, microvilli, and plicae circularis function to A) liberate hormones. B) promote peristalsis. C) produce bile. D) increase surface area for absorption. E) stimulate chemical digestion.

D) increase surface area for absorption.

*73) Emulsification A) converts small lipid droplets into larger droplets. B) occurs in the gallbladder. C) chemically digests lipids. D) increases surface area for lipid digestion. E) involves enzymes.

D) increases surface area for lipid digestion.

26) Saliva A) is produced only when there is food in the mouth. B) increases ulceration in the mouth. C) is responsible for peristalsis in the mouth. D) moistens food and begins starch digestion in the mouth. E) does not prevent bacterial infection in the mouth.

D) moistens food and begins starch digestion in the mouth.

69) The digestive juice that contains enzymes capable of digesting all major food groups is ________. A) gastric juice B) biliary juice C) salivary juice D) pancreatic juice E) hepatic juice

D) pancreatic juice

Identify the part of the stomach labeled: T

Duodenum

Describe the enzymatic digestion of carbohydrates

During digestion, polysaccharides break down into smaller chains and finally into disaccharides and monosaccharides. Disaccharides break down into monosaccharides. -A minor amount of carbohydrate digestion begins in the oral cavity with the partial digestion of starches by salivary amylase. -Continues in the stomach until the food is well mixed with acid, which inactivates salivary amylase. -Resumed in the small intestine by pancreatic amylase. A series of disaccharidases that are bound to the microvilli of the intestinal epithelium digest disaccharides into monosaccharides. The monosaccharides glucose and galactose are taken up into intestinal epithelial cells by symport, powered by a Na+ gradient. -The monosaccharide fructose is taken up by facilitated diffusion. Once inside the intestinal epithelial cell, monosaccharides are transported by facilitated diffusion to the capillaries of the intestinal villi and carried by the hepatic portal system to the liver, where the nonglucose sugars are converted to glucose. Glucose enters the cells through facilitated diffusion.

*21) Which of the following organs is retroperitoneal? A) Pancreas B) Ascending colon C) Duodenum D) Descending colon E) All of the choices are correct.

E) All of the choices are correct

61) Functions of the liver include ________. A) production of many blood proteins B) interconversion of nutrients C) detoxification of harmful chemicals D) bile production E) All of the choices are correct

E) All of the choices are correct

*62) Hepatocytes A) phagocytize cells. B) form phospholipids and hydroxylate vitamin D. C) convert ammonia to urea. D) remove sugar from the blood and store it as glycogen. E) All of the choices are correct.

E) All of the choices are correct.

*66) Which of the following apply to the small intestine? A) Secretions from the liver and pancreas enter this organ. B) Segmentation contractions occur in this organ. C) Both digestion and absorption occur in this organ. D) Mixing and propulsion of chyme. E) All of the choices are correct.

E) All of the choices are correct.

14) What is the function of enteric sensory neurons? A) Detect changes in chemical composition of digestive tract contents B) Stimulate or inhibit smooth muscle contraction in the digestive tract C) Stimulate or inhibit glandular secretion in the digestive tract D) Detect stretch of the digestive tract wall E) Both "Detect changes in chemical composition of digestive tract contents" and "Detect stretch of the digestive tract wall" are correct.

E) Both "Detect changes in chemical composition of digestive tract contents" and "Detect stretch of the digestive tract wall" are correct.

*12) The enteric plexus A) is found in the mucosa. B) consists of the myenteric plexus and the celiac plexus. C) helps control movement and secretions of the digestive tract. D) contains parasympathetic neurons. E) Both "Helps control movement and secretions of the digestive tract" and "Contains parasympathetic neurons" are correct

E) Both "Helps control movement and secretions of the digestive tract" and "Contains parasympathetic neurons" are correct

Identify the part of the stomach labeled: N

Esophagus

Identify the part of the stomach labeled: K

Mucosa

Identify the part of the stomach labeled: L

Muscularis

Identify the part of the stomach labeled: A

Pyloric part

Identify the part of the stomach labeled: B

Pyloric sphincter

Identify the part of the stomach labeled: M

Rugae

Identify the part of the stomach labeled: J

Submucosa

Describe the route of transport for water-soluble and lipids-soluble molecules

Water-soluble digestion products enter the hepatic portal system and are transported to the liver. Lipids are coated with proteins and transported into lymphatic capillaries called lacteals. The lacteals are connected by lymphatic vessels to the thoracic duct, which empties into the left subclavian vein. The protein-coated lipid products then travel in the circulation to adipose tissue or to the liver.

2) Which of the following is NOT an accessory organ of the digestive tract? A) Esophagus B) Salivary glands C) Pancreas D) Gallbladder

A) Esophagus

67) Cholecystokinin is produced by endocrine cells of the ________. A) stomach B) small intestine C) pancreas D) large intestine E) liver

B) small intestine

42) Which of the following events occurs because of the low pH of the stomach? A) Activation of salivary amylase B) Enhanced carbohydrate digestion C) Proper environment for functioning of pepsin D) Protein synthesis E) Lipid digestion

C) Proper environment for functioning of pepsin

*54) Where does the majority of nutrient absorption occur? A) The stomach and duodenum B) The duodenum and ileum C) The jejunum and duodenum D) The ileum and jejunum

C) The jejunum and duodenum

Identify the part of the stomach labeled: C

Cardiac sphincter

25) Inflammation of the gums is called ________. A) dental caries B) pyorrhea C) halitosis D) gingivitis

D) gingivitis

11) The myenteric plexus is found in the ________ of the digestive tract wall. A) mucosa B) serosa C) submucosa D) muscularis E) adventitia

D) muscularis

Identify the part of the stomach labeled: D

Fundus