BY 32 – SPRING 2000
Section 6143
EXAM 1
NAME ___________________________________
Instructions: Record your answers directly on this sheet by circling the
correct response. For each question,
choose the single best response.
1. In
reference to homeostasis, the presence of regulatory mechanisms provide for
stabile conditions within: (C)
a.
the
lumen (i.e. internal space) of organs of the GI tract.
b.
airways
of the respiratory system.
c.
extracellular
fluids.
d.
all
of the above.
2. Blood
pressure is one example of a physiological variable that is subject to negative
feedback control. In this negative
feedback loop, cardiovascular centers in the brainstem represent which of the following components?
(C)
a.
The
physiological variable
b.
The
sensor
c.
The
feedback controller
d.
The
effector
3. In a
positive feedback system, the effectors cause changes in the physiological
variable which: (A)
a.
reinforce
the initial disturbance.
b.
oppose
the initial disturbance.
c.
cause
the variable to return to its set-point.
d.
both
b and c.
4. Of the
various types of intercellular communication, which of the following allow for
the direct passage of a regulatory molecule from one cell to the next? (A)
a.
gap
junctions
b.
the
endocrine system
c.
the
nervous system.
d.
all
of the above
5. Besides
thyroid hormones, which of the following interacts with receptors located in
the nucleus of target cells? (D)
a.
The
parathyroid hormone
b.
The
catecholamines
c.
The
anterior pituitary hormones
d.
Aldosterone
6. Following
receptor activation by the hormone ADH (antidiuretic hormone), the enzyme that
is responsible for cleaving PIP2 into IP3 (inositol
triphosphate) and DAG (diacylglycerol) is called: (C)
a.
protein
kinase A.
b.
adenylate
cyclase.
c.
phospholipase
C.
d.
protein
kinase C.
7. ADH
secretion will increase in response to which of the following conditions? (A)
a.
A
fall in blood pressure
b.
Drinking
several alcoholic beverages
c.
Drinking
several glasses of water
d.
An
increase in blood volume
8. The two
non-trophic hormones released from the anterior pituitary gland are prolactin
and: (D)
a.
Thyroid
stimulating hormone (TSH).
b.
Follicle
stimulating hormone (FSH).
c.
Adrenocorticotropin
hormone (ACTH).
d.
Growth
hormone (GH).
9. The
growth promoting effects of growth hormone are mediated by insulin-like growth
factors also known as: (B)
a.
somatostatins.
b.
somatomedins.
c.
somatotropins.
d.
prolactin.
10.
Follicular cells of the thyroid gland increase production of thyroid
hormones in response to increased: (A)
a.
thyroid
stimulating hormone (TSH).
b.
thyroid
inhibiting hormone (TIH).
c.
increased
T3 and T4 in blood.
d.
all
of the above.
11.
Hyposecretion of the adrenal cortex involving both aldosterone and
cortisol is called: (B)
a.
Grave’s
disease.
b.
Addison’s
disease.
c.
Aldosteronism.
d.
Diabetes
insipidus
12. Insulin
is released: (C)
a.
from a
(alpha) cells of the pancreas.
b.
in
response to a fall in blood glucose.
c.
in
response to an increase in blood glucose.
d.
in
response to insulin releasing hormone.
13. Target
cells for calcitonin are found in: (D)
a.
the
kidney.
b.
the
GI tract
c.
the
pituitary
d.
in
bone.
14. The
accessory GI organ that stores bile is called: (B)
a.
the
pancreas.
b.
the
gallbladder.
c.
the
parotid.
d.
the
vermiform appendix.
15. The
process by which nutrient molecules are taken up from the GI tract lumen across
the epithelium is called: (C)
a.
digestion.
b.
secretion.
c.
absorption.
d.
reabsorption.
16. The
structure through which blood vessels and nerves pass to and from peritoneal
organs is called: (B)
a.
an
adventitia.
b.
a
mesentery.
c.
a
peritoneum.
d.
the
greater omentum.
17.
Sandwiched between the epithelium and muscularis mucosa is a layer
called the: (C)
a.
submucosa.
b.
adventitia.
c.
lamina
propria.
d.
serosa.
18. The
uvula is a structure that is attached to the: (D)
a.
lip.
b.
tongue.
c.
gums.
d.
soft
palate.
19. Which of
the following best describes the histology of the lower 1/3 of the esophagus?
(A)
a.
The
epithelium is stratified squamous, and the muscularis externus is exclusively
smooth muscle.
b.
The
epithelium is simple columnar, and the muscularis externus is exclusively
skeletal muscle.
c.
The
epithelium is stratified squamous, and the muscularis externus is exclusively
skeletal muscle.
d.
The
epithelium is simple columnar, and the muscularis externus is exclusively
smooth muscle.
20. Which of
the following structures disappears upon distension of the stomach? (D)
a.
The
gastric pits
b.
The
gastric glands
c.
The
plicae circulares
d.
The
rugae
21. Parietal
cells are most often found in the: (B)
a.
cardiac
portion of the stomach.
b.
body
of the stomach.
c.
pyloric
region of the stomach.
d.
esophagus.
22. At the
termination of the small intestine is a smooth muscle sphincter called the: (B)
a.
pyloric
sphincter.
b.
ileocecal
valve.
c.
lower
esophageal sphincter.
d.
internal
anal sphincter.
23.
Throughout the small intestine, the intestinal glands are called: (D)
a.
Brunner’s
glands.
b.
the
submandibular glands.
c.
gastric
glands.
d.
crypts.
24. Within
the large intestine, the longitudinal layer of the muscularis externa is
organized into three longitudinal bands called: (C)
a.
haustra.
b.
epiploic
appendages.
c.
teniae
coli.
d.
the
greater omentum.
25. The duct
of which of the following exocrine glands empties to the vestibule of the
mouth? (A)
a.
The
parotid
b.
The
submandibular
c.
The
sublingual
d.
The
pancreas
26. Which of
the following exocrine glands contains the highest relative proportion of
mucous acini? (C)
a.
The
parotid
b.
The
submandibular
c.
The
sublingual
d.
The
pancreas
27. The
process of chemical digestion begins in the mouth with the action of: (A)
a.
amylase.
b.
pepsin.
c.
gastrin.
d.
mucus.
28. Compared
to baseline secretion rates, maximum parasympathetic stimulation will cause
amylase secretion into saliva to: (A)
a.
increase.
b.
remain
unchanged.
c.
decrease.
29. Striated
duct cells modify the composition by adding bicarbonate and extracting which of
the following ions? (B)
a.
Ca2+
b.
Na+
c.
K+
d.
Mg2+
30. During
the oral phase of swallowing, (A)
a.
the
upper esophageal sphincter is closed.
b.
a
peristaltic wave is generated in the esophagus.
c.
the
lower esophageal sphincter is open.
d.
all
of the above.
31. During
the esophageal phase of swallowing, (D)
a.
a
peristaltic wave conducts along the esophagus.
b.
the
upper esophageal sphincter is closed.
c.
the
lower esophageal sphincter opens just before food enters the stomach.
d.
all
of the above.
32. Gastrin
secretion is stimulated by: (B)
a.
histamine.
b.
caffeine.
c.
emotional
trauma.
d.
excessive
acidity (that is pH < 2).
33. The
hormone with the most potent inhibitory effect on gastric secretion is: (C)
a.
gastrin.
b.
CCK.
c.
secretin.
d.
gastric
inhibitory peptide (GIP).
34. The
proteolytic enzymes of the pancreas are released into the duodenum in inactive
form. The first step in their
activation involves: (C)
a.
the
formation of chymopepsin in the presence of stomach acid.
b.
the
formation of chymotrypsin from trypsin.
c.
the
conversion of trypsinogen to trypsin by an enzyme called enterokinase.
d.
interaction
with intrinsic factor.
35. CCK is
released from enteroendocrine cells of the small intestine in response to: (C)
a.
parasympathetic
stimulation.
b.
acidic
chyme in the duodenum.
c.
chyme
containing amino acids and fatty acids in the duodenum.
d.
bicarbonate
in the small intestine.
36. CCK acts
on the: (B)
a.
gallbladder
causing it to relax.
b.
sphincter
of Oddi causing it to relax.
c.
hepatocytes
causing them to increase bicarbonate production.
d.
the
pancreas to increase bicarbonate production.
37. During
the defecation reflex, (D)
a.
stretch
receptors in the rectum activate sympathetic nerves.
b.
the
internal anal sphincter contracts.
c.
the
intra-abdominal pressure decreases.
d.
the
final phase involves conscious relaxation of the external anal sphincter.
38. Bile
salts act to: (A)
a.
emulsify
fats.
b.
break
down lipids into fatty acids and glycerol.
c.
inhibit
micelle formation.
d.
all
of the above.
39. Lactose
intolerance involves a lack of: (B)
a.
lactose.
b.
lactase.
c.
glucose.
d.
amylase.
40. Most
water absorption takes place in the: (C)
a.
esophagus.
b.
stomach.
c.
small
intestine.
d.
large
intestine.