Download Midterm 2 – MC Key - Creighton Biology

Name: __________________________
Biology 449 - Animal Physiology
Spring 2008
Midterm 2 – MC Key
Fill in your scantron form as follows:
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Write and bubble in your name in the upper left (last name first).
Follow any additional instructions provided in class.
Sign your form on the upper right. By so doing you verify that you are abiding
by Creighton’s policy on academic honesty.
Multiple choice: As always, choose the best answer for each multiple-choice question.
Answer on your scantron form. Each question is worth 3 points.
1. For a chemical messenger to be classified as a hormone, it must
a.
b.
c.
d.
e.
promote the release of another chemical messenger.
be released from a modified neuron.
trigger a response in all cells in the body.
be carried in the blood.
consist of amino acids.
2. Which of the following secretes steroid hormones?
a.
b.
c.
d.
e.
Adrenal cortex
Adrenal medulla
Anterior pituitary
Gonads
Two of the above. (a and d)
3. If you learned that a newly-discovered chemical messenger activated intracellular receptors,
you could reasonably assume that it
a.
b.
c.
d.
e.
was a peptide hormone.
was an autocrine agent.
was lipophilic.
was a tropic hormone.
activated a G-protein complex.
4. Cortisol levels would be expected to rise in response to
a.
b.
c.
d.
e.
decreased food intake.
increased rate of growth.
increased sexual activity.
increasing age.
bad karma.
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5. In class, we learned about the formation of goiters as the result of iodine insufficiency, but
other causes are possible. In fact, anything that results in overstimulation of the thyroid
gland can cause it to hypertrophy. Based on what you know about the thyroid hormone
pathways, which of the following would not tend to result in increased size of the thyroid
gland?
a.
b.
c.
d.
e.
high levels of thyrotropin releasing hormone
low levels of thyroid stimulating hormone.
low levels of thyroxin and triiodothyronine.
All of the above would tend to increase the size of the thyroid gland.
None of the above would tend to increase the size of the thyroid gland.
6. Growth hormone levels are normally at their daily peak
a.
b.
c.
d.
e.
about an hour or two before each meal.
during each meal.
about an hour or two after each meal.
shortly after going to sleep.
shortly after waking up.
7. Which of the following patterns would you expect to see in an otherwise normal 25-year-old
given regular injections of large amounts of growth hormone?
a. The person would develop brittle bones.
b. The person would show thickening of the bones, but no change in bone length.
c. The person would show growth in bone length, but no change in thickness of the
bones.
d. The person would show growth in both bone length and thickness.
e. There would be no effect of increased growth hormone at this age.
8. If allowed to shorten fully, sarcomeres reach a length at which they no longer produce any
net force. The main reason for this is
a.
b.
c.
d.
e.
the thin filaments encounter the “bald spot” on the thick filament.
the thin filaments start bending back on themselves.
the thick filaments are being compressed by the Z-line of the sarcomere.
the thin and thick filaments no longer overlap.
ATP can no longer enter the sarcomere.
9. In skeletal muscle, an action potential in the sarcolemma (muscle membrane) of a fiber is
normally initiated by
a.
b.
c.
d.
e.
the release of Ca2+ from the sarcoplasmic reticulum.
neurotransmitter from a motor neuron opening ligand-gated ion channels.
neurotransmitter from a motor neuron activating G-protein complexes.
the stretching of t-tubules.
action potentials from adjacent fibers passing into the fiber via gap junctions.
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10. Which of the following molecules has a conformation that is directly affected by membrane
voltage?
a.
b.
c.
d.
e.
Ca2+-ATPase
Dihydropyridine
Myosin
Ryanodine
Troponin
11. Relative to a twitch contraction, a tetanic contraction produces
a.
b.
c.
d.
e.
about the same force for about the same duration.
a greater force for about the same duration.
about the same force for a longer duration.
a greater force for a longer duration.
nothing but pain.
12. An individual fast glycolytic muscle fiber can produce more power than a slow oxidative
fiber (although for only a short time) because
a.
b.
c.
d.
e.
it has fast rather than slow myosin ATPase.
it has more space dedicated to myofibrils rather than mitochondria.
it is larger in diameter.
glycolysis produces energy more rapidly than oxidative phosphorylation.
All of the above are true.
13. As a whole muscle is called on to produce more and more force, the last motor units recruited
will consist of
a.
b.
c.
d.
e.
relatively small numbers of slow oxidative fibers.
relatively large numbers of slow oxidative fibers.
relatively small numbers of fast glycolytic fibers.
relatively large numbers of fast glycolytic fibers.
Motor units within a muscle do not differ in their composition.
14. If 10.0 liters/min is flowing through the left heart, which of the following will also have
10 liters/min flowing through it/them?
a.
b.
c.
d.
e.
The systemic arteries
The systemic capillaries
The right heart
Two of the above will have 10 liters/min flowing through them.
All of the above will have 10 liters/min flowing through them.
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15. When does blood enter the ventricles of the heart?
a. During the beginning of ventricular diastole, due to pressure that built up in the
venous system.
b. During the middle of ventricular diastole, when ventricular pressure is lowest.
c. During the end of ventricular diastole, when the atria contract.
d. Throughout the diastolic period.
e. Which one is the ventricle again?
16. Which of the following events occurs first during ventricular systole?
a.
b.
c.
d.
e.
Isovolemic contraction
The atrioventricular valves close
The atrioventricular valves open
The semilunar valves close
The semilunar valves open
17. Which of the following correctly describes the relationship among the cardiovascular
variables shown?
a.
b.
c.
d.
e.
MAP = (HR  SV)  TPR
MAP = (HR  SV)  TPR
TPR = (HR  SV)  MAP
TPR = (HR  SV)  TPR
TPR = (HR  SV)  MAP
18. According to Poiseuille’s Law, a tripling of the diameter of a blood vessel would increase the
flow through the vessel by
a.
b.
c.
d.
e.
three-fold.
nine-fold.
27-fold.
81-fold.
243-fold.
19. A type of substance that does not move between the capillaries and the interstitial space is
a.
b.
c.
d.
e.
dissolved gases.
small cations.
small anions.
glucose.
plasma proteins.
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20. Movement of lymph through the lymphatic system to the superior vena cava relies mainly on
a.
b.
c.
d.
e.
chambered-heart type pumping by the lymph nodes.
the high positive pressure in the interstitial fluid.
peristalsis and pressure from surrounding skeletal muscles.
negative pressure in the venous system.
osmotic differentials between blood in the veins and lymph in the lymphatic system.
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