Deck 41: Structure and Function of the Digestive System

Question 1

In the mouth and stomach, salivary a-amylase initiates the digestion of which nutrients?

A)Proteins
B)Carbohydrates
C)Fats
D)Fiber

Answer 1

Carbohydrates

Question 2

Which gastric cells secrete hydrochloric acid and intrinsic factor?

A)Parietal
B)Chief
C)G
D)D

Answer 2

Parietal

Question 3

Which gastric hormone inhibits acid and pepsinogen secretion, as well as decreases the release of gastrin?

A)Motalin
B)Histamine
C)Somatostatin
D)Acetylcholine

Answer 3

Somatostatin

Question 4

Which statement best describes the gastrointestinal tract?

A)The gastrointestinal tract is a muscular tube that transports food from the mouth to the stomach.
B)The gastrointestinal tract is a hollow tube that extends from the mouth to the anus.
C)The gastrointestinal tract is a baglike structure that propels partially digested food (chyme).
D)The gastrointestinal tract is 5 m long and consists of three segments.

Question 5

What is the formation of water-soluble molecules to facilitate the absorption of the byproducts of lipid hydrolysis accomplished by?

A)Micelles
B)Phospholipase
C)Chylomicrons
D)Colipase

Question 6

Exposure to which substance protects the mucosal barrier of the stomach?

A)Prostaglandins
B)Acetylcholine
C)Helicobacter pylori
D)Regurgitated bile

Question 7

The student asks the professor why water and electrolytes are transported in both directions through tight junctions and intercellular spaces rather than across cell membranes. What response by the professor is best?

A)The intercellular hydrostatic pressure is inadequate to push the water and electrolytes across the cell membranes.
B)A balance of cations and ions among the electrolytes on each side of the cell membranes cannot be maintained.
C)The epithelial cell membranes are formed of lipids that are hydrophobic and therefore repel water.
D)Receptors on those cell membranes are occupied with a diffusion of amino acids and monosaccharides.

Question 8

Glucose transport enhances the absorption of which electrolyte?

A)Sodium
B)Phosphate
C)Potassium
D)Chloride

Question 9

Which cells in the stomach secrete histamine?

A)Oxyntic
B)Chief
C)D
D)Enterochromaffin-like

Question 10

What is the primary source of physiologic iron?

A)Transferrin from plasma
B)Pepsin form pepsinogen
C)Bile from bilirubin
D)Heme from animal protein

Question 11

What effect is a result of inhibiting the parasympathetic nervous system with a drug such as atropine?

A)Salivation becomes thinner.
B)Salivation decreases.
C)The pH of saliva changes.
D)Digestive enzymes are inhibited.

Question 12

Which water-soluble vitamin is absorbed by passive diffusion?

A)Vitamin B₆
B)Vitamin B₁
C)Vitamin K
D)Folic acid

Question 13

Food enters the stomach via which orifice or sphincter?

A)Cardiac
B)Upper esophageal
C)Gastric
D)Fundal

Question 14

Where in the small intestines are lymphocytes, plasma cells, and macrophages produced?

A)Brush border
B)Microvilli
C)Lamina propria
D)Crypts of Lieberkühn

Question 15

The ileum and jejunum are suspended by folds of the peritoneum that contain an extensive vascular and nervous network. What are these folds called?

A)Ligament of Treitz
B)Mesentery
C)Auerbach folds
D)Lamina propria

Question 16

Saliva contains which immunoglobulin (Ig)?

A)IgA
B)IgE
C)IgG
D)IgM

Question 17

Which pancreatic enzyme is responsible for the breakdown of carbohydrates?

A)Trypsin
B)Amylase
C)Lipase
D)Chymotrypsin

Question 18

What process is capable of increasing both intrathoracic and intraabdominal pressure, thereby facilitating defecation?

A)Relaxation of the internal anal sphincter
B)Intestinal peristalsis
C)Valsalva maneuver
D)Ileogastric reflex

Question 19

Which enzyme breaks down protein-forming polypeptides in the stomach?

A)Acetylcholine
B)Pepsin
C)Gastrin
D)Secretin

Question 20

A professor has taught a class of students about the characteristics of vitamin B₁₂. Which statement by a student demonstrates a need for more education?

A)Vitamin B₁₂ is absorbed in the terminal ileum.
B)Vitamin B₁₂ is absorbed in its free (unbound) form in small amounts.
C)Vitamin B₁₂ is necessary for platelet maturation.
D)Vitamin B₁₂ binds to intrinsic factor.

Question 21

Which water-soluble vitamins are dependent on sodium for absorption? (Select all that apply.)

A)Pantothenic acid
B)Vitamin B₁
C)Niacin
D)Vitamin B₁₂
E)Folic acid

Question 22

What is the role of the normal intestinal bacterial flora?

A)Metabolizing bile salts, estrogens, and lipids
B)Breaking down proteins into amino acids
C)Facilitating the motility of the colon
D)Metabolizing aldosterone and insulin

Question 23

Which hormones are involved in the relaxation of the stomach's fundus during swallowing? (Select all that apply.)

A)Progesterone
B)Glucagon
C)Motilin
D)Gastrin
E)Cholecystokinin

Question 24

A professor has been teaching a class on gastrointestinal function. Which statement by a student indicates the need for more education?

A)Within 30 min of eating, the gallbladder forces bile into the stomach.
B)Cholinergic branches of the vagus nerve mediate gallbladder contraction.
C)Cholecystokinin provides hormonal regulation of gallbladder contraction.
D)The sphincter of Oddi controls the flow of bile from the gallbladder.

Question 25

Which elements in saliva protect against tooth decay? (Select all that apply.)

A)Salivary a-amylase
B)Ptyalin
C)Mucin
D)Exogenous fluoride
E)A pH of 7.4

Question 26

Gastric emptying is delayed by the presence of which substances? (Select all that apply.)

A)Solids
B)Carbohydrates
C)Nonisotonic solutions
D)Bacteria
E)Fats

Question 27

Which vitamin facilitates the absorption of iron by the epithelial cells of the duodenum and jejunum?

A)B₆
B)C
C)E
D)B₁₂

Question 28

Which structure synthesizes clotting factors and the vitamin K necessary for hemostasis?

A)Colon
B)Spleen
C)Gallbladder
D)Liver

Question 29

Which hormones are involved in regulating gastric motility by lowering the threshold potential of muscle fibers? (Select all that apply.)

A)Estrogen
B)Secretin
C)Somatostatin
D)Gastrin
E)Motilin

Question 30

The process of conjugation of bilirubin in the liver is best described as which transformation?

A)Unconjugated (fat-soluble) bilirubin into urobilinogen
B)Unconjugated (fat-soluble) bilirubin into conjugated (water-soluble) bilirubin
C)Conjugated (water-soluble) bilirubin into unconjugated (fat-soluble) bilirubin
D)Conjugated (water-soluble) bilirubin into urobilinogen

Question 31

How are Kupffer cells best described?

A)Natural killer cells that produce interferon-gamma (IFN-g)
B)Contractile and therefore capable of regulating the sinusoid blood flow
C)Bactericidal and therefore central to innate immunity
D)Able to metabolize estrogen, progesterone, and androgens

Question 32

What requirements are necessary for calcium to be absorbed through the ileum at concentrations of less than 5 mmol/L? (Select all that apply.)

A)Receptor site on the ileum
B)Vitamin D₃
C)Vitamin K
D)Carboxypeptidase
E)A carrier protein

Question 33

Bilirubin is a byproduct of the destruction of which aged cells?

A)Platelets
B)Protein
C)Leukocytes
D)Erythrocytes

Question 34

Which statement, made by a student, is correct regarding the state of the intestinal tract at birth?

A)The intestinal tract is colonized by Escherichia coli.
B)The intestinal tract is sterile.
C)Clostridium welchii is present in but in very small numbers.
D)Streptococcus colonization in the intestinal tract has begun.

Question 35

What information does the student learn regarding the functions of the pancreas? (Select all that apply.)

A)Cholecystokinin stimulates the release of pancreatic enzymes.
B)Bilirubin and S cells inhibit the secretion of pancreatic enzymes.
C)Pancreatic polypeptide is released after eating.
D)Acetylcholine (ACh) is liberated from the pancreatic branches of the vagus nerve.
E)ACh stimulates the release of pancreatic enzymes.

Question 36

How many days does it take for the entire epithelial population of the small intestines to be replaced?

A)30 to 45
B)15 to 25
C)7 to 15
D)4 to 7