q&a carbohydrate

Question 1

Which of the following substances is
released from neurons in the GI tract and
produces smooth muscle relaxation?

Answer 1

Vasoactive intestinal peptide (VIP)

Question 2

Which of the following is the site of
sec r e t i o n
o f
i n t r i n s i c f a c t o r

Answer 2

Gastric fundus

Question 3

Vibrio cholerae causes diarrhea because it

Answer 3

increases Cl– secretory channels in crypt
cells

Question 4

Cholecystokinin (CCK) has some
gastrin- like properties because both
C C K
and gastrin

Answer 4

have five identical C-terminal amino
acids

Question 5

Which of the following is transported in
intestinal epithelial cells by a Na+-dependent
cotransport process?

Answer 5

Alanine

Question 6

A 49-year-old male patient with severe
Crohn’s disease has been unresponsive to drug therapy and undergoes ileal resection.
After the surgery, he will have steatorrhea
because

Answer 6

micelles do not form in the intestinal
lumen

Question 7

Cholecystokinin (CCK) inhibits

Answer 7

gastric emptying

Question 8

Which of the following abolishes “receptive relaxation” of the stomach?

Answer 8

Vagotomy

Question 9

Secretion of which of the following
substances is inhibited b y low p H

Answer 9

Gastrin

Question 10

Which of the following is the site of
secretion of gastrin?

Answer 10

Gastric antrum

Question 11

Micelle formation is necessary for the
intestinal absorption of

Answer 11

vitamin D

Question 12

Which of the following changes occurs
during defecation?

Answer 12

Internal anal sphincter is relaxed

Question 13

Which of the following is characteristic
of saliva?

Answer 13

Hypotonicity relative to plasma

Question 14

Which of the following substances is
secreted in response to an oral glucose
load?

Answer 14

Glucose-dependent insulinotropic
p e p t i d e ( G I P

Question 15

Which of the following is true about the
secretion from the exocrine pancreas?

Answer 15

Pancreatic enzyme secretion is
increased by cholecystokinin (CCK)

Question 16

Which of the following substances must
be further digested before it can be
absorbed by specific carriers in intestinal
cells?

Answer 16

Sucrose

Question 17

Slow waves in small intestinal smooth
muscle cells are

Answer 17

oscillating resting membrane potentials

Question 18

Slow waves in small intestinal smooth
muscle cells are

Answer 18

involves contraction of smooth muscle
behind the food bolus and relaxation of
smooth muscle in front of the bolus

Question 19

A patient with a duodenal ulcer is treated successfully with the drug cimetidine. The basis for cimetidine’s inhibition of gastric
H+ secretion is that it

Answer 19

blocks H2 receptors on parietal cells

Question 20

Which of the following substances
inhibits gastric emptying?

Answer 20

Cholecystokinin (CCK)

Question 21

When parietal cells are stimulated, they
secrete

Answer 21

HCl and intrinsic factor

Question 22

A patient with Zollinger–Ellison syn
drome would be expected to have which of the following changes?

Answer 22

Peptic ulcer disease

Question 23

Which of the following is the site of
Na+–bile acid cotransport?

Answer 23

Ileum

Question 24

A 46-year-old woman has hirsutism,
hyperglycemia, obesity, muscle wasting, and
increased circulating levels of adrenocorticotropic hormone (ACTH). The most likely
cause of her symptoms is

Answer 24

primary overproduction of ACTH
(Cushing’s disease)

Question 25

Blood levels of which of the following
substances is decreased in Graves’ disease?

Answer 25

Thyroid-stimulating hormone (TSH)

Question 26

Which of the following hormones acts by
an inositol 1,4,5-triphosphate (IP3)–Ca2+
mechanism of action?

Answer 26

Gonadotropin-releasing hormone
(GnRH)

Question 27

A 39-year-old man with untreated dia
betes mellitus type I is brought to the emer
gency room. An injection of insulin would
be expected to cause an increase in his

Answer 27

blood pH

Question 28

Which of the following pancreatic secre
tions has a receptor with four subunits, two
of which have tyrosine kinase activity?

Answer 28

Insulin

Question 29

A 43-year-old man eats a meal consisting of 40 percent
protein, 10 percent fat, and 50 percent carbohydrate.
Thirty minutes later the man feels the urge to defecate.
Which reflex results in the urge to defecate when the
duodenum is stretched?