pretest 2002 gastro p117-145 Flashcards
What is correct regarding small intestinal motility?
contractile activity is initiated in response to bowel wall distention
chronic administration of what type of drug would lead to sustained increase in serum gastrin levels?
proton pump inhibitor
What is correct regarding gastric emptying?
Vagotomy decreases accommodation of the proximal stomach
Vitamin B12 is absorbed primarily in the
Ileum
The principal paracrine secretion involved in the inhibitory feedback regulation of gastric acid secretion is
somatostatin
What is the putative inhibitory neurotransmitter responsible for relaxation of gastrointestinal smooth muscle?
vasoactive intestinal peptide (VIP)
Cholera toxin causes diarrhea by inhibiting
neutral NaCl absorption in the small intestine
What describes water and electrolyte absorption in the GI tract?
The majority of absorption occurs in the jejunum
Hypokalemic metabolic acidosis can occur with excess fluid loss from the
colon
Which gastrointestinal motor activity is most affected by vagotomy?
orad stomach accommodation
The hormone involved in the initiation of the migration motor complex is
motilin
the rate of gastric emptying increases with an increase in
intragastric volume
Basal acid output is increased by
Alkalinization of the antrum
What process applies to the proximal stoamch?
Accommodation
After secretion of trypsinogen into the duodenum, the enzyme is converted into its active from, trypsin, by
Enteropeptidase
The major mechanism for absorption of sodium from the small intestine is
neural NaCl absorption
Pharmacological blockade of histamine H2 receptors in the gastric mucosa
inhibits both gastrin- and acetylcholine-mediated secretion of acid
Removal of proximal segments of the small intestine results in a decrease in
pancreatic enzyme secretion
Gas within the colon is primarily derived from what source?
Fermentation of undigested oligosaccharides by bacteria
Removal of the pyloric sphincter is associated with
an increase in the rate of gastric emptying of solids
Removal of the terminal ileum will result in
an increase in the water content of the feces
Vitamins synthesized by intestinal bacteria and absorbed in significant quantities include
Folic acid
What is correct regarding the colon?
Absorption of Na+ in the colon is under hormonal (aldosterone) control
Contraction of the gallbladder is correctly described by
that is occurs in response to cholecystokinin
Acidification of the duodenum will
decrease gastric emptying
What is correct regarding the small intestinal crypt cells
they are responsible for net NaCl and water secretion
In contrast to secondary esophageal peristalsis, primary esophageal peristalsis is characterized by
it has an oropharyngeal phase
Absorption of fat-soluble vitamins requires
pancreatic lipase
What sugar is absorbed from the small intestine by facilitated diffusion
fructose
Nearly all binding of cobalamin (vitamin B12) to intrinsic factor occurs in the
duodenum
Secondary esophageal peristalsis
is accompanied by lower esophageal sphincter relaxation
At concentrations present in the diet, which vitamin is absorbed primarily by diffusion
Vitamin D
As compared to long-chain fatty acids, medium chain fatty acids
can be used as a source of calorie in patients with malabsorptive disease
Severe inflammation of the ileum may be accompanied by
decreased bile acid pool size
What statement about the process of vitamin B12 absorption is correct?
absorption may be reduced in a patient with pancreatic insufficiency
Patients may experience nausea and a sense of early satiety following
A vagotomy of the distal stomach
The origin of electrical slow wave activity in gastrointestinal tract smooth muscle is
the interstitial cells of Cajal
True/False: Maximal acid output may be increased in a patient with duodenal ulcer disease
true
The major factor that protects the duodenal mucosa from damage by gastric acid is
pancreatic bicarbonate secretion
Bicarbonate absorption from the upper small intestine is closely coupled with
Na/H exchange
True/False: Bile acid synthesis is catalyzed by the microsomal enzyme 7 alpha-hydroxylase
true
Withdrawal from chronic administration of an anti secretory compound is followed by rebound gastric acid hypersecretion. What drug could account fro the observed result?
a proton pump inhibitor
the migrating motor complex in humans
requires an intact intrinsic nervous system for coordinated propagation
The delivery of chyme into the proximal small intestine will
increase small intestine segmentation
A person is found to have an increased basal and maximal acid outputs, ,decreased serum calcium levels, and microcytic anemia. Inflammation in what area of the gastrointestinal tract would explain these findings?
duodenum
what best describes water electrolyte absorption in the gastrointestinal tracct?
osmotic equilibration of chyme occurs in the duodenum
the paracrine secretion responsible for inhibiting gastric acid secretion is
somatostatin
a medical student presents to the ER with a two-day history of severe vomiting and orthostatic hypotension. what kind of metabolic abnormalities would you expect?
hypokalemic, hypochloremic, metabolic alkalosis
the metabolic effects of insulin include
decreased lipolysis
in contrast to secretory diarrhea, osmotic diarrhea
is characterized by an increase in stool osmolarity
The macrolide antibiotic erythromycin is associated with gastrointestinal disturbances related to increased motility. The antibiotic works by binding to receptors on nerves and smooth muscle that recognize the gastrointestinal hormone…
Motilin
The transport protein responsible for entry of glucose into the intestinal enterocyte called
SGLT1
Short-chain fatty acid absorption occurs almost exclusively from the
colon
True/False: Regarding medium-chain fatty acids, they are more water-soluble than long-chain fatty acids.
True
