Ch 23: The Digestive System

1) The relatively unchanging pressure in a filling stomach is due to
the contraction of the stomach oblique muscle layer.

FALSE

2) The circular folds of the small intestine enhance absorption by
causing the chyme to spiral, rather than to move in a straight line,
as it passes through the small intestine.

TRUE

3) Gastric accommodation is an example of smooth muscle plasticity.

TRUE

4) Some of the microbes that often invade other organs of the body
are rarely found in the stomach. The reason for this is the presence
of HCl.

TRUE

5) Stellate macrophages are found in the liver and are responsible
for removing bacteria and worn-out cells.

TRUE

6) The pharyngeal-esophageal phase of swallowing is involuntary and
is controlled by the swallowing center in the thalamus and lower pons.

FALSE

7) All the chemical and mechanical phases of digestion from the mouth
through the small intestine are directed toward changing food into
forms that can pass through the epithelial cells lining the mucosa
into the underlying blood and lymphatic vessels.

TRUE

8) Pepsinogen is the precursor to the gastric enzyme for protein
digestion and is secreted by the parietal cells.

FALSE

9) The only essential function of the stomach is to begin the
digestion of proteins.

FALSE

10) The major role of absorption in the ileum is to reclaim bile
salts to be recycled back to the liver.

TRUE

11) The peritoneum is the most extensive serous membrane in the body.

TRUE

12) Peyer's patches are found in the submucosa of the distal end of
the small intestine.

TRUE

13) The submucosal nerve plexus provides the major nerve supply to
the GI tract wall and controls GI motility.

FALSE

14) The major means of propulsion through the alimentary canal is peristalsis.

TRUE

15) Dentin anchors the tooth in place.

FALSE

16) The digestive function of the liver is to produce bile.

TRUE

17) The pancreas has both an endocrine and an exocrine function.

TRUE

18) Another term for swallowing is deglutition.

TRUE

19) The intrinsic ability of visceral smooth muscle to exhibit the
stress-relaxation response is termed plasticity.

TRUE

20) The stomach's contractile rhythm is set by pacemaker cells found
in the spinal cord.

FALSE

21) The major stimulus for production of intestinal fluid is
distention or irritation of the intestinal mucosa by hypertonic or
acidic chyme.

TRUE

22) Most nutrients are absorbed through the mucosa of the intestinal
villi by active transport.

TRUE

23) Severe diarrhea can diminish potassium ion absorption.

TRUE

24) Mumps is an inflammation of the parotid glands caused by myxovirus.

TRUE

25) Fats significantly delay the emptying of the stomach through
hormonal and neuronal signals.

TRUE

26) The soft palate reflexively opens the nasopharynx to allow the
passage of food, which is now called a bolus.

FALSE

27) When swallowing, the epiglottis covers the larynx.

TRUE

28) Most gastric ulcers are due to excessive production of
hydrochloric acid.

FALSE

1) The enterohepatic circulation reabsorbs bile salts in the distal
portion of the small intestine (ileum). All of the following
statements about the enterohepatic circulation are true except one.
Select the statement below that is not true of the enterohepatic
circulation? A) Reabsorbing bile salts in the ileum gives more time to
emulsify lipid and aid in their absorption within a greater length of
the small intestine. B) All of the components of bile are recycled by
this circulation. C) Reabsorption of bile salts reduces the need to
synthesize new bile salts. D) The reabsorption of bile salts allows
them to be reused within new bile.

B

2) 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) Digestions must happen first for metabolism to
follow it. C) Metabolism comprises all of the chemical reactions
preformed with in the body while digestion is only the breakdown of
food within the G.I. Tract. D) Digestion requires enzymes for it to
take place while metabolism does not necessarily need or use them.

C

3) Which of the following is least involved in the mechanical
breakdown of food, digestion or absorption of nutrients? A) the oral
cavity B) the esophagus C) large intestine D) the small ingestion

B

4) Which of the organs listed below is involved in all of the
following processes: secretion, mechanical breakdown of food,
digestion and absorption? A) the stomach B) the esophagus C) the
sigmoid colon D) the large intestines

A

5) 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 alkaline
secretion of the small intestine aid in the growth of bacteria and
must be controlled. B) The body will actively excrete pathogens out
the body, into the digestive system to be removed from the body in
feces. C) The huge numbers of bacteria living in the large intestine
must be prevented from entering the lumen of the small intestine and
being absorbed with food's nutrients into the blood stream. D) The
digestive systems first and foremost job is to digest and absorb
nutrients so it puts off immunity for last.

C

6) Bile salts bind at their hydrophobic regions to large fat globules
within the chyme that enters the duodenum. Bile salts break up the fat
globule into smaller fat droplets. This role of bile salts is best
described as ________. A) lipid emulsification B) lipid absorption C)
lipid ingestion D) lipid digestion

A

7) A doctor consulting a patient that recently has had their gall
bladder removed would likely advise ________. A) increasing
unsaturated fats while eliminating trans fats in their diets B) a low
to no carb diet C) fewer, but larger meals D) eating foods that are
low in fat

D

8) A ruptured appendix is life threatening because ________. A) it is
likely to cause severe internal bleeding B) the large intestine will
no longer be able to receive digested material from the small
intestine C) loss of the appendix's function will cause an immune
deficiency in the digestive system D) it is likely to cause massive
infection of the abdominopelvic cavity

D

9) All but one of the following is a function of the low pH found in
the stomach. Select the description below that does not reflect a role
of stomach acid. A) The stomach's acid catabolically breaks down food
stuffs in preparation for absorption. B) Stomach acid denatures
proteins making the poly peptide chain more accessible to pepsin
digestive enzymes. C) Many potentially harmful bacteria will be
prevented entry to the small intestine by stomach acid. D) Low pH
converts pepsinogen to its active form of pepsin, preventing the
protease enzyme from digesting the cells that produce it.

A

10) Fat absorption through the plasma membrane of epithelial cells
________. A) Is accomplished by cotransporters that use the
concentration gradient of Na+ outside of the cells B) requires
vesicular, active transport of the relatively large fatty acids and
monoglyceride C) occurs by simple diffusion because lipids are able to
penetrate the hydrophobic fatty acid tails within the plasma membrane
D) requires enzymes attached to the brush border to further breakdown
the fats

C

11) Select the best explanation for why protease enzymes are secreted
in inactive forms. A) Inactive enzymes will simply be expelled with
the feces if no protein is present in the digesting food, this will
help to conserve energy. B) The immunoglobulins protecting the
digestive tract would be digested without proper regulation of protein
digesting enzymes. C) The enzymes would digest each other if they were
not properly regulated. D) The cells producing inactive enzymes are
themselves protected from the enzymes until they are safely within the
lumen of the GI tract.

D

12) Select the description below that illustrates a difference
between a sphincter and circular muscle. A) A sphincter is a
thickening of circular muscle that can prevent the movement of
digesting materials while circular muscle is involved in propulsion
digesting material. B) Sphincters are found throughout the GI tract
while circular muscle is found only in the proximal portion of the GI
tract. C) A sphincter is composed of smooth muscle while circular
muscle is composed of skeletal muscle tissue. D) Sphincters are found
in the proximal portion of the GI tract while circular muscle is found
in the distal portions.

A

13) In the enteric nervous system, a long reflexive pathway has an
advantage over a short reflexive pathway in the fact that ________. A)
long reflexive pathways last much longer than short reflexive pathways
B) long reflexive pathways can respond throughout the entire length of
the GI tract while short reflexive pathways can only respond in the
proximal end C) long reflexive pathways are quicker to respond than
short reflexive pathways D) long reflexive pathways can be stimulated
by things outside of the GI tract

D

14) The sight of food can trigger a series of events that results in
the release of gastric juice. All but one of the following is true in
regards to the previous statement. Select the one answer that is not
true. A) This prepares the stomach for food before its arrival in the
stomach. B) This is an example of a long reflexive pathway. C) The
motor nerves of this pathway are part of the sympathetic division of
the autonomic nervous system. D) The cerebral cortex, hypothalamus and
medulla oblongata are all involved in processing the stimulatory information.

C

15) All of the following are true of swallowing (deglutition) except
one. Select the statement that is not true of swallowing. A) The
involuntary portion of swallowing takes place in the pharynx. B) The
mouth, pharynx and esophagus all take part in swallowing. C) The
epiglottis assists in propelling food into the trachea. D) The
voluntary phase of swallowing takes place within the mouth.

C

16) Some antacid drugs block histamine receptors, resulting in
reduction of the production and excretion of stomach acid. These drugs
have the biggest effect on which of the following? A) surface
epithelial cells B) chief cells C) mucous neck cells D) parietal cells

D

17) Generally the hormones secretin and cholecystokinin which are
released by duodenal enteroendocrine cells will ________. A) speed the
churning of the stomach B) increases the output of stomach acid C)
speed the activity of the jejunum D) slow the activities of the stomach

D

18) Generally the hormones secretin and cholecystokinin which are
released by duodenal enteroendocrine cells will ________. A) decrease
the activities of the accessory digestive organs B) increases stomach
emptying C) increase the force of stomach contractions D) increase the
release of digestive enzymes and bile

D

19) Select the one response below that would not result from a drug
that blocks histamine receptors in the cells lining the stomach. A)
It would reduce the symptoms of heartburn. B) It would cause the
release of secretin and cholecystokinin. C) It would lower the
activity of parietal cells. D) It would raise the pH of the stomach.

B

20) Proteins entering the stomach act as a buffer raising pH. Rising
pH stimulates the activity of G-cells in the lining of the stomach.
All of the following but one will occur. Select the statement below
that would not occur. A) More stomach acid will be produced and
secreted. B) A positive feedback response will be initiated and G-cell
activity will continue to go up. C) Protein digestion will be
enhanced. D) Digestive enzymes will be released.

B

21) The mechanical and chemical receptors that control digestive
activity are located ________. A) in the walls of the tract organs B)
in the glandular tissue that surround the organ lumen C) in the oral
cavity D) in the pons and medulla

A

22) The function of the hepatic portal circulation is to ________. A)
return glucose to the general circulation when blood sugar is low B)
carry toxins to the kidney for disposal through the urinary tract C)
distribute hormones throughout the body D) collect absorbed nutrients
for metabolic processing in the liver

D

23) The chemical and mechanical processes of food breakdown are
called ________. A) secretion B) ingestion C) absorption D) digestion

D

24) When we ingest large molecules such as lipids, carbohydrates, and
proteins, they must undergo catabolic reactions whereby enzymes split
these molecules. This series of reactions is called ________. A)
mechanical breakdown B) absorption C) secretion D) chemical digestion

D

25) The sheets of peritoneal membrane that hold the digestive tract
in place are called ________. A) mucosal lining B) lamina propria C)
serosal lining D) mesenteries

D

26) From the esophagus to the anal canal, the walls of every organ of
the alimentary canal are made up of the same four basic layers.
Arrange them in order from the lumen. A) serosa, mucosa, submucosa,
and muscularis externa B) mucosa, submucosa, muscularis externa, and
serosa C) submucosa, serosa, muscularis externa, and mucosa D)
muscularis externa, serosa, mucosa, and submucosa

B

27) Which of the following is not a factor that helps create the
stomach mucosal barrier? A) replacing of damaged epithelial mucosa
cells B) thick coating of bicarbonate-rich mucus C) secretion of
pepsinogen D) tight junctions of epithelial mucosa cells

C

28) What part of the tooth bears the force and resists the friction
of chewing? A) crown B) enamel C) cementum D) pulp

B

29) The capillaries that nourish the epithelium and absorb digested
nutrients lie in the ________. A) adventitia B) lamina propria C)
submucosa D) serosa

B

30) Choose the incorrect statement regarding bile. A) Bile functions
to emulsify fats. B) Bile contains enzymes for digestion. C) Bile
functions to carry bilirubin formed from breakdown of worn-out RBCs.
D) Bile is both an excretory product and a digestive secretion.

B

31) The absorptive effectiveness of the small intestine is enhanced
by increasing the surface area of the mucosal lining. Which of the
following accomplish this task? A) the vast array of digestive enzymes
B) the rugae and haustra C) villi, and microvilli D) Brunner's glands
and Peyer Patches

C

32) Select the statement that is true concerning primary teeth. A)
There are 20 primary teeth, and by 24 months of age most children have
all 20. B) There are 27 primary teeth, and the molars are permanent.
C) There are 32 primary teeth, and by 36 months of age, most children
have all 32. D) There are 24 primary teeth, and no new primary teeth
appear after 13 months.

A

33) Which of the following is true concerning the number and type of
permanent teeth? A) There are 27 permanent teeth, and the first molars
are usually the last to emerge. B) There are 32 permanent teeth, and
the wisdom teeth are the last to emerge. C) The number of upper
permanent teeth is not equal to the number of lower permanent teeth.
D) The number of permanent teeth is always equal to the number of
primary teeth.

B

34) Which of the following is not true of saliva? A) moistens food
and aids in compacting of the bolus B) cleanses the mouth C) contains
enzymes that begin the breakdown of carbohydrates D) contains acids
which aid in chemical digestion

D

35) The solutes contained in saliva include ________. A) mucin,
lysozyme, electrolytes, salts, and minerals B) only proteases and
amylase C) electrolytes, digestive enzyme, mucin, lysozyme, wastes,
and IgA D) only salts and minerals

C

36) The bolus is liquefied in the ________ and it is now called
chyme. A) esophagus B) stomach C) small intestine D) mouth

B

37) Peristaltic waves are ________. A) churning movements of the
gastrointestinal tract that aid in mechanical breakdown of chyme B)
segmental regions of the gastrointestinal tract C) waves of muscular
contractions that propel contents from one point to another D)
pendular movements of the gastrointestinal tract

C

38) Pepsinogen, an inactive digestive enzyme, is secreted by the
________. A) parietal cells of the duodenum B) goblet cells of the
small intestine C) Brunner's glands D) chief cells of the stomach

D

39) You have just eaten a meal high in complex carbohydrates. Which
of the following enzymes will help to digest the meal? A) amylase B)
trypsin C) gastrin D) cholecystokinin

A

40) The ducts that deliver bile and pancreatic juice from the liver
and pancreas, respectively, unite to form the ________. A)
hepatopancreatic ampulla B) bile canaliculus C) pancreatic acini D)
portal vein

A

41) Short-chain triglycerides found in foods such as butterfat
molecules in milk are split by a specific enzyme in preparation for
absorption. Which of the following enzymes is responsible? A) pepsin
B) amylase C) lipase D) chymotrypsin

C

42) Hepatocytes do not ________. A) store fat-soluble vitamins B)
produce digestive enzymes C) process nutrients D) detoxify toxic chemicals

B

43) Chief cells ________. A) produce gastrin B) produce mucin C)
produce pepsinogen D) produce HCl

C

44) Chemical digestion reduces large complex molecules to simpler
compounds by the process of ________. A) catabolism B) fermentation C)
mastication D) anabolism

A

45) The ________ contains lobules with sinusoids (lined with
macrophages) that lead to a central venous structure. A) stomach B)
spleen C) liver D) pancreas

C

46) Digestion and absorption of which of the following would be
affected the most if the liver were severely damaged? A) starches B)
proteins C) lipids D) carbohydrates

C

47) The dental formula for an adult is 2-1-2-3. What does the 1 stand
for? A) premolar tooth B) canine tooth C) molar tooth D) incisor tooth

B

48) The lamina propria is composed of ________. A) dense irregular
connective tissue B) dense regular connective tissue C) reticular
connective tissue D) loose connective tissue

D

49) Which of the following is (are) not important as a stimulus in
the gastric phase of gastric secretion? A) distention B) peptides C)
low acidity D) carbohydrates

D

50) The function of goblet cells is to ________. A) provide
protection against invading bacteria and other disease-causing
organisms that enter the digestive tract in food B) secrete buffers in
order to keep the pH of the digestive tract close to neutral C)
produce mucus that protects parts of the digestive organs from the
effects of powerful enzymes needed for food digestion D) absorb
nutrients from digested food and store them for future use

C

51) Which of the following is an essential role played by large
intestine bacteria? A) absorb bilirubin B) synthesize vitamins C and D
C) fermentation of indigestible carbohydrates D) produce gas

C

52) Nervous control of gastric secretion is provided by ________. A)
somatic neurons in the spinal cord B) the vagus nerve and enteric
plexus C) the reticulospinal and vestibulospinal tracts D) the
rubrospinal tracts

B

53) Which of the following are types of papillae on the tongue that
contain taste buds? A) palatine and circumvallate B) fungiform,
circumvallate, and filiform C) circumvallate and filiform D) fungiform
and circumvallate

D

54) Which of the following produce intrinsic factor? A) mucous neck
cells B) zymogenic cells C) enteroendocrine cells D) parietal cells

D

55) Which of the following enzymes would be most active in the
presents of a high concentrations of protein fragments? A) lipase B)
trypsin C) amylase D) dextrinase

B

56) A child with restricted tongue movement may have a surgery that
involves the cutting of the ________. A) lingual frenulum B) uvula C)
palatine tonsils D) terminal sulcus

A

57) What stomach secretion is necessary for normal hemoglobin
production in RBCs? A) pepsinogen B) gastric lipase C) intrinsic
factor D) HCl

C

58) Select the correct statement about the regulation of gastric
secretion. A) Gastric secretion can be stimulated before food has
entered the mouth. B) The presence of food in the stomach prevents
hormonal control of gastric secretion. C) Vagus stimulation of the
stomach results in decreased secretion of gastric juice. D) Gastric
secretion is enhanced by very low pH (below a pH of 2).

A

59) Paneth cells ________. A) secrete hormones B) secrete digestive
enzymes C) secrete bicarbonate ions D) secrete enzymes that kill bacteria

D

60) Select the correct statement about absorption. A) Eighty percent
of ingested materials have been absorbed by the end of the large
intestine. B) In the rare case that intact, whole proteins are
transported across the mucosal endothelium, an immune response may be
generated. C) Carbohydrates diffuse across the mucosal endothelium and
are then actively transported into blood capillaries. D) Amino acid
transport is linked to chloride transport.

B

61) Select the correct statement about electrolyte absorption. A)
Chlorine ion absorption is coupled to glucose and amino acid
transport. B) If vitamin B is not present, calcium is not absorbed. C)
Iron and calcium are absorbed mostly by the duodenum. D) Potassium
moves across the epithelium by active transport.

C

62) The ingestion of a meal high in fat content would cause which of
the following to occur? A) This type of food would cause secretion of
gastrin to cease, resulting in faster gastric emptying. B) Increased
production of trypsinogen. C) Bile would be released from the
gallbladder to emulsify the fat in the duodenum. D) The acid
secretions from the stomach would be sufficient to digest this food
but may cause heartburn.

C

63) Hormones or paracrines that inhibit gastric secretion include
________. A) histamine B) secretin C) ACh D) gastrin

B

64) Which of these is not part of the splanchnic circulation? A)
hepatic portal vein B) superior mesenteric artery C) celiac artery D)
inferior vena cava

D

65) Which of these is not a component of saliva? A) lysozyme B)
metabolic waste C) defensins D) a cyanide derivative

D