Deck 16: A--The Digestive System

Question 1

The intrinsic nerve plexuses

A) produce spontaneous depolarization of the smooth muscle cells in the wall of the digestive tract
B) are located in the mucosa
C) coordinate local activity in the digestive tract
D) produce spontaneous depolarization of the smooth muscle cells in the wall of the digestive tract and coordinate local activity in the digestive tract
E) none of these

Answer 1

C

Question 2

Proteins are primarily digested to and absorbed as

A) amino acids
B) polypeptides
C) fatty acids and glycerol
D) monosaccharides
E) vitamins

Answer 2

A

Question 3

The BER refers to the

A) basic eating reflex ensuring that food is moved along the digestive tract at an appropriate rate.
B) basic electrical rhythm consisting of spontaneous, rhythmic, wavelike fluctuations in membrane potential.
C) basic emptying reflex, which governs the rate of gastric emptying.
D) bowel evacuation reflex or defecation reflex.
E) None of these

Answer 3

B

Question 4

Fats are digested to

A) amino acids
B) cellulose
C) fatty acids and glycerol
D) fructose
E) monosaccharides

Question 5

Which tissue layer provides for primary digestive motility?

A) mucosa
B) submucosa
C) muscularis mucosae
D) muscularis externa
E) mesentery

Question 6

Which statement regarding control of digestive processes is incorrect?

A) Short reflexes influence motility and secretion in localized areas.
B) All elements of the short reflexes are contained within the digestive organ's wall.
C) Hormones play a role.
D) Osmoreceptors monitor the acidity of the luminal contents.
E) There are stretch receptors in the walls of digestive organs.

Question 7

Carbohydrates are absorbed as

A) polysaccharides
B) disaccharides
C) monosaccharides
D) amino acids
E) fatty acids

Question 8

Which of the following organs is not a digestive tract organ?

A) esophagus
B) stomach
C) pancreas
D) small intestine
E) large intestine

Question 9

Digestive motility

A) is accomplished by smooth muscle contractions
B) is accomplished by smooth and voluntary muscle contractions
C) may be propulsive in nature
D) is accomplished by smooth and voluntary muscle contractions and may be propulsive in nature.
E) is accomplished by smooth muscle contractions and may be propulsive in nature

Question 10

Which statement is incorrect?

A) In general, parasympathetic stimulation is excitatory to the digestive system.
B) Parasympathetic innervation to the digestive tract comes primarily through the vagus nerve.
C) Parasympathetic innervation is part of the extrinsic nerve supply to the digestive tract.
D) Parasympathetic stimulation of the salivary glands produces a saliva rich in mucus.
E) Parasympathetic stimulation increases salivary, gastric, pancreatic, and biliary secretion.

Question 11

Which statement is incorrect?

A) The myenteric plexus is located in the submucosa.
B) The intrinsic plexuses innervate smooth muscle cells and exocrine and endocrine glands.
C) The plexuses are influenced by extrinsic nerves.
D) The plexuses coordinate local digestive tract activity.
E) There are two major networks of nerve fibers forming the plexuses of the gut.

Question 12

The serosa is the

A) abdominal cavity containing the stomach
B) blood supply to the stomach
C) inner lining of the digestive tract
D) layer of smooth muscle of the digestive tract
E) outer connective-tissue covering of the digestive tract

Question 13

The enteric nervous system includes

A) the myenteric plexus.
B) the submucosal plexus.
C) vagal nerve efferents.
D) the myenteric plexus and the submucosal plexus.
E) the myenteric plexus and vagal nerve efferents.

Question 14

Mixing movements

A) promote digestion by mixing food with digestive juices
B) facilitate absorption by exposing luminal contents to absorptive surfaces
C) take place only in the stomach
D) promote digestion by mixing food with digestive juices and facilitate absorption by exposing luminal contents to absorptive surfaces
E) all of these

Question 15

Milk sugar is digested to

A) glucose and fructose
B) glucose and galactose
C) sucrose and glucose
D) maltose
E) cellulose

Question 16

Secretions from digestive organs include

A) enzymes
B) bile
C) mucus
D) hormones
E) all of these

Question 17

Which is the primary absorptive organ of the digestive system?

A) salivary glands
B) oral cavity
C) stomach
D) small intestine
E) colon

Question 18

Digestion of polysaccharides

A) is accomplished using enzymes
B) utilizes hydrolysis
C) utilizes dehydration
D) is accomplished using enzymes and utilizes hydrolysis
E) is accomplished using enzymes and utilizes dehydration

Question 19

Chewing increases which of the following secretions?

A) Salivary secretion
B) Gastric secretion
C) Pancreatic secretion
D) Salivary secretion and Gastric secretion
E) All of these

Question 20

9,500 ml of fluid is absorbed from the digestive tract daily. The ultimate source of most of this fluid is

A) food and fluid ingested during meals.
B) stored within secretory cells of the digestive tract.
C) the plasma.
D) the accessory digestive organs.
E) metabolic water.

Question 21

Swallowing

A) includes the movement of the bolus from the mouth to the stomach
B) includes only the movement of the bolus from the mouth to the esophagus
C) is a sequentially programmed, multiple response, all-or-none reflex
D) includes the movement of the bolus from the mouth to the stomach and is a sequentially programmed, multiple response, all-or-none reflex
E) includes only the movement of the bolus from the mouth to the esophagus and is a sequentially programmed, multiple response, all-or-none reflex

Question 22

The gastroesophageal sphincter is normally closed to prevent

A) air from entering the esophagus during breathing
B) gastric contents from refluxing into the esophagus
C) vomiting
D) esophageal leaking into the stomach
E) food from entering the pharynx

Question 23

Which of the following is entirely under nervous control and has no hormonal regulatory component?

A) salivary secretion
B) gastric secretion
C) pancreatic secretion
D) liver secretion
E) none of these (all have a hormonal regulatory component)

Question 24

Receptive relaxation refers to relaxation of the

A) pharyngoesophageal sphincter during swallowing
B) pyloric sphincter when the duodenum is prepared to receive the chyme
C) external anal sphincter when the individual is receptive to the defecation reflex
D) stomach as it starts to fill, thereby allowing an increase in volume with very little increase in pressure
E) none of these

Question 25

Which of the following factors will not influence the rate at which a meal will empty from the stomach?

A) fat in the duodenum
B) acid in the duodenum
C) caffeine in the duodenum
D) hypertonicity of the duodenal contents
E) distention of the duodenum

Question 26

The swallowing center is located in the

A) cerebral cortex
B) medulla
C) hypothalamus
D) throat
E) spinal cord

Question 27

The pharyngoesophageal sphincter is normally closed to prevent

A) air from entering the esophagus during breathing
B) gastric contents from refluxing back into the esophagus
C) vomiting
D) esophageal secretions from leaking into the stomach
E) food from entering the pharynx

Question 28

Salivary secretion is

A) entirely under neural control (i.e., there is no hormonal control of salivary secretion).
B) a passive secretion.
C) stimulated by the parasympathetic nervous system and inhibited by the sympathetic nervous system.
D) entirely under neural control (i.e., there is no hormonal control of salivary secretion)and a passive secretion.
E) entirely under neural control (i.e., there is no hormonal control of salivary secretion)and stimulated by the parasympathetic nervous system and inhibited by the sympathetic nervous system.

Question 29

Which statement is incorrect?

A) Salivation is entirely under neural control.
B) Parasympathetic stimulation and sympathetic stimulation both increase salivary secretion.
C) The acquired salivary reflex occurs upon stimulation of chemoreceptors and/or pressure receptors in the mouth.
D) Parasympathetic stimulation produces a watery saliva rich in enzymes.
E) The salivary center is located in the medulla.

Question 30

If peristalsis in the esophagus is insufficient to carry an especially large bolus of food through the esophagus to the stomach, what happens to dislodge this trapped food?

A) A secondary peristaltic wave is initiated by the swallowing center.
B) A secondary peristaltic wave is initiated by distention of the esophagus, mediated by the intrinsic nerve plexuses.
C) The food remains in the esophagus until the swallowing mechanism is voluntarily initiated once again.
D) Increased esophageal mucus secretion occurs to lubricate the stuck bolus so that it can slide to the stomach.
E) Food never becomes stuck in the esophagus because it is very distensible.

Question 31

Which of the following factors is the most potent stimulus for inhibition of gastric motility?

A) fat in the duodenum
B) acid in the duodenum
C) acid in the stomach
D) distention of the stomach
E) hypertonicity of the duodenal contents

Question 32

Which of the following is not a component of saliva?

A) amylase
B) mucus
C) pepsin
D) lysozyme
E) water

Question 33

During the oropharyngeal phase of swallowing, food is prevented from

A) reentering the mouth by elevation of the uvula
B) entering the nasal passages by closure of the nasopharyngeal sphincter
C) entering the trachea primarily by the epiglottis blocking the opening between the vocal cords
D) reentering the mouth by elevation of the uvula and entering the trachea primarily by the epiglottis blocking the opening between the vocal cords
E) none of these

Question 34

The major chemical digestive activity occurring in the stomach is

A) digestion of starch
B) digestion of protein
C) digestion of fat
D) absorption of monosaccharides
E) digestion of vitamins

Question 35

What helps prevent food from entering the trachea during swallowing?

A) elevation of the uvula
B) contraction of the pharyngeal muscles
C) positioning of the tongue
D) tight apposition of the vocal cords over the glottis
E) elevation of the epiglottis over the pharyngoesophageal sphincter

Question 36

Which of the following is not a function of saliva?

A) Facilitates swallowing
B) Serves as a solvent for molecules that stimulate taste buds
C) Dissolves glucose to facilitate its absorption by the oral mucosa
D) Has antibacterial action
E) Aids speech

Question 37

Secondary peristaltic waves in the esophagus

A) occur when a large or sticky bolus becomes stuck in the esophagus
B) are coordinated by the swallowing center
C) are coordinated by extrinsic nerve signals
D) occur when a large or sticky bolus becomes stuck in the esophagus, and are coordinated by the swallowing center
E) occur when a large or sticky bolus becomes stuck in the esophagus, and are coordinated by extrinsic nerve signals

Question 38

Which of the following is accomplished by chewing?

A) Grinding and breaking up food
B) Mixing food with saliva to facilitate swallowing
C) Reflexively increasing salivary and gastric secretions
D) Reflexively increasing pancreatic and bile secretions
E) All of these

Question 39

What prevents food from entering the nasal passages during swallowing?

A) elevation of the uvula
B) contraction of the pharyngeal muscles
C) positioning of the tongue
D) tight apposition of the vocal cords over the glottis
E) elevation of the epiglottis over the nasopharynx

Question 40

Gastric mixing

A) occurs primarily in the body of the stomach
B) occurs as a result of the stomach's contents being tumbled back and forth in the fundus because of vigorous peristaltic contractions
C) mixes the food with gastric secretions to convert it to a finely divided liquid form known as chyme
D) occurs as a result of the stomach's contents being tumbled back and forth in the fundus because of vigorous peristaltic contractions. and mixes the food with gastric secretions to convert it to a finely divided liquid form known as chime
E) All of these

Question 41

Which factor below does not slow down gastric activities?

A) enterogastric reflex
B) enterogastrones
C) secretin
D) gastrin
E) cholecystokinin

Question 42

Bile acts on

A) distention of the stomach
B) gastrin
C) carbohydrate in the stomach
D) fat in the duodenum
E) fat in the stomach

Question 43

The pyloric gland area of the stomach antrum secretes

A) histamine
B) gastrin
C) intrinsic factor
D) histamine and gastrin
E) histamine and intrinsic factor

Question 44

Stomach acid is neutralized

A) in the duodenum
B) with trypsin
C) by solutions secreted from the antrum
D) in the duodenum and with trypsin
E) none of these

Question 45

As food leaves the stomach, gastric secretion is reduced. Which of the following factors does not contribute to this reduction?

A) fat in the duodenum
B) low gastric pH
C) distention of the duodenum
D) high concentration of acid in the stomach or duodenum
E) pepsinogen in the duodenum

Question 46

The chief cells of the gastric mucosa secrete

A) bicarbonate ions
B) HCl
C) pepsinogen
D) sucrase
E) trypsin

Question 47

The pyloric sphincter is located between the

A) esophagus and stomach
B) oral cavity and esophagus
C) large intestine and rectum
D) small intestine and large intestine
E) stomach and small intestine

Question 48

Inhibition of gastric secretion following a meal is accomplished by

A) the enterogastric reflex
B) inhibition of the pyloric gland area by vagal stimulation
C) a high concentration of H⁺, which directly inhibits the release of gastrin
D) the enterogastric reflex and a high concentration of H⁺, which directly inhibits the release of gastrin
E) all of these

Question 49

Hormones acting in the small intestine include

A) secretin and cholecystokinin
B) secretin and gastrin
C) cholecystokinin and gastrin
D) all of these
E) none of these

Question 50

The pyloric gland area of the stomach antrum

A) secretes gastrin
B) is inhibited when gastric pH falls too high
C) is stimulated by the presence of glucose
D) all of these
E) is inhibited when gastric pH falls too high and by the presence of glucose.

Question 51

Which of the following statements concerning HCl secretion by the stomach is correct?

A) HCl inactivates salivary amylase and the pancreatic enzymes.
B) HCl activates pepsinogen.
C) It establishes a low pH in the stomach.
D) Oxyntic cells are responsible for it.
E) All of these.

Question 52

Which of the following breakfasts would remain in the stomach the longest?

A) toast, orange juice, and coffee
B) black coffee
C) fried eggs, bacon, and hash browns
D) bowl of cereal with skim milk
E) boiled egg, toast, and juice

Question 53

Which statement regarding gastric motility and emptying is incorrect?

A) Increased fluidity allows more rapid emptying.
B) Presence of acid and fat in the stomach initiates the enterogastric reflex.
C) Increased gastric volume stimulates motility.
D) Vagal activity stimulates motility.
E) Distention of the stomach initiates short reflexes.

Question 54

During the cephalic phase of gastric secretion:

A) Thinking about, seeing, and smelling food reflexively increases gastric secretion.
B) Vagal stimulation of the gastric glands occurs.
C) Gastrin is released.
D) Chewing food reflexively increases gastric secretion.
E) All of these.

Question 55

Peristaltic antral contractions

A) occur at a rate of 3/min
B) are responsible for emptying food into the duodenum
C) are responsible for mixing food and gastric enzymes within the antrum
D) are the result of smooth muscle contractions
E) all of these

Question 56

The parietal cells of the gastric mucosa secrete

A) HCl
B) pepsinogen
C) intrinsic factor
D) HCl and pepsinogen
E) HCl and intrinsic factor

Question 57

Pernicious anemia can occur when:

A) The stomach has been removed.
B) The terminal ileum has been removed.
C) There is a deficiency of intrinsic factor.
D) All of these
E) The stomach has been removed and there is a deficiency of intrinsic factor.

Question 58

Which of the following is a precursor to an enzyme that functions in the stomach?

A) pepsinogen
B) HCl
C) intrinsic factor
D) gastrin
E) mucus

Question 59

Intrinsic factor is

A) secreted by the parietal cells in the stomach
B) necessary for absorption of vitamin B₁₂
C) abundant in pernicious anemia
D) secreted by the parietal cells in the stomach and necessary for absorption of vitamin B₁₂
E) none of these

Question 60

After pepsinogen is activated, it

A) autocatalytically activates more pepsinogen
B) activates the pancreatic proteolytic enzymes in the duodenal lumen after gastric emptying has occurred
C) inhibits the pyloric gland area in a negative-feedback fashion
D) autocatalytically activates more pepsinogen and activates the pancreatic proteolytic enzymes in the duodenal lumen after gastric emptying has occurred
E) none of these

Question 61

Which of the following are functions of aqueous NaHCO₃ secreted by the pancreas into the duodenum?

A) neutralization of acidic gastric contents emptied into the duodenum
B) prevention of irritation of the duodenal mucosa
C) active digestion of fat molecules into fatty acids
D) neutralization of acidic gastric contents emptied into the duodenum, and prevention of irritation of the duodenal mucosa
E) none of these

Question 62

Chymotrypsinogen

A) is activated by enterokinase
B) once activated, is involved in protein digestion
C) is secreted by the endocrine pancreas
D) all of these
E) none of these

Question 63

Which of the following is not a function of the liver?

A) metabolic processing of carbohydrates, proteins, and fats
B) secretion of proteolytic digestive enzymes
C) detoxification and/or degradation of body wastes, hormones, drugs, and foreign compounds
D) synthesis of plasma proteins essential to the clotting process
E) storage of glycogen, fats, iron, copper, and many vitamins

Question 64

During vomiting

A) The diaphragm contracts.
B) The abdominal muscles contract.
C) The stomach contracts.
D) The diaphragm and the abdominal muscles contract.
E) The abdominal muscles and the stomach contracts.

Question 65

Which of the following substances is absorbed by the stomach?

A) glucose
B) caffeine
C) aspirin
D) amino acids
E) fatty acids

Question 66

Which of the following is an active proteolytic enzyme?

A) pepsinogen
B) chymotrypsinogen
C) procarboxypeptidase
D) secretin
E) none of these

Question 67

Which statement regarding control of pancreatic secretion is correct?

A) Gastrin stimulates release of neutralization solution.
B) CCK stimulates release of enzymes.
C) Secretin stimulates release of bicarbonate.
D) All of these.
E) CCK stimulates release of enzymes, and secretin stimulates release of bicarbonate.

Question 68

Venous flow into the liver is via the

A) hepatic vein
B) hepatic portal system
C) sinusoidal system
D) mesenteric system
E) none of these

Question 69

Select the incorrect statement about the pancreas.

A) It has endocrine tissue.
B) It has exocrine tissue.
C) It secretes an alkaline fluid.
D) It secretes pepsinogen.
E) It secretes trypsinogen.

Question 70

Alcohol

A) inhibits gastric secretion
B) can be absorbed more rapidly from the small intestine than from the stomach
C) inhibits gastric emptying through the enterogastric reflex
D) inhibits gastric secretion and can be absorbed more rapidly from the small intestine than from the stomach
E) all of these

Question 71

Bile salts

A) aid fat digestion
B) aid fat absorption through micelle formation
C) are made in the gall bladder
D) aid fat digestion and absorption through micelle formation
E) all of these

Question 72

The typical coloration of the feces is due to

A) bile salts
B) undigested cellulose
C) aqueous NaHCO₃ secretion
D) modified bilirubin
E) disintegrated epithelial cells

Question 73

Which statement is incorrect?

A) Trypsinogen is secreted in an inactive form.
B) Pancreatic amylase digests carbohydrate.
C) Pancreatic lipase is responsible for triglyceride digestion.
D) Except for trypsinogen, other proteolytic enzymes are secreted in active form.
E) Trypsinogen is activated by enterokinase.

Question 74

The hormone secretin is released by endocrine cells in the duodenal mucosa in response to

A) distention of the stomach
B) carbohydrate in the duodenum
C) acid in the duodenum
D) gastrin secreted by the pyloric gland area of the stomach
E) none of these

Question 75

Which of the following does not occur during vomiting?

A) The diaphragm contracts.
B) The abdominal muscles contract.
C) The stomach contracts.
D) Respiration is inhibited.
E) The glottis is closed.

Question 76

Which of the following is the most important stimulus for contraction of the gallbladder?

A) CCK
B) mechanical contraction of the small intestine
C) sympathetic stimulation
D) an increase in bile secretion by the liver
E) bile salts

Question 77

Which statement is correct?

A) The most potent stimulus for secretin secretion is the presence of fat in the duodenum.
B) Secretin stimulates pancreatic enzyme secretion.
C) Secretin stimulates the secretion of bicarbonate.
D) Secretin stimulates the acinar cells.
E) None of these.

Question 78

Cholecystokinin

A) is secreted by the endocrine portion of the pancreas
B) stimulates pancreatic enzyme secretion
C) causes contraction of the gallbladder
D) stimulates pancreatic enzyme secretion and causes contraction of the gallbladder
E) none of these

Question 79

Peptic ulcers

A) are usually caused by excessive neural stimulation
B) are usually caused by bacterial infection
C) compromise the mucosal barrier and stomach wall
D) are usually caused by excessive neural stimulation and by bacterial infection
E) are usually caused by bacterial infection and compromise the mucosal barrier and stomach wall

Question 80

Which of the following stimulates gallbladder contraction?

A) CCK
B) secretin
C) sympathetic stimulation
D) CCK and secretin
E) CCK and sympathetic stimulation