Cardiovascular Physiology
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3. Which solute is found in the highest concentration in plasma?
4. Summarize the production, life span, and destruction of
erythrocytes.
5. What are the routes of iron gain, loss, and distribution, and
how is iron recycled when erythrocytes are destroyed?
6. Describe the control of erythropoietin secretion and the effect
of this hormone.
7. State the relative proportions of erythrocytes and leukocytes in
blood.
8. Diagram the derivation of the different blood cell lines.
9. Describe the sequence of events leading to platelet activation
and aggregation, and the formation of a platelet plug. What
helps keep this process localized?
10. Diagram the clotting pathway beginning with
prothrombin.
11. What is the role of platelets in clotting?
12. List all the procoagulant effects of thrombin.
13. How is the clotting cascade initiated? How does the extrinsic
pathway recruit the intrinsic pathway?
14. Describe the roles of the liver and vitamin K in clotting.
15. List three ways in which clotting is limited.
16. Diagram the fi brinolytic system.
17. How does fi brin help initiate the fi brinolytic system?
Chapter 12 Test Questions
(Answers appear in Appendix A.)
1. Which of the following contains blood with the lowest oxygen
content?
a. aorta
b. left atrium
c. right ventricle
d. pulmonary veins
e. systemic arterioles
2. If other factors are equal, which of the vessels below would have
the lowest resistance?
a. length = 1 cm, radius = 1 cm
b. length = 4 cm, radius = 1 cm
c. length = 8 cm, radius = 1 cm
d. length = 1 cm, radius = 2 cm
e. length = 0.5 cm, radius = 2 cm
3. Which of the following correctly ranks pressures during
isovolumetric contraction of a normal cardiac cycle?
a. left ventricular > aortic > left atrial
b. aortic > left atrial > left ventricular
c. left atrial > aortic > left ventricular
d. aortic > left ventricular > left atrial
e. left ventricular > left atrial > aortic
4. Which of the following is
not
characteristic of the body’s
capillaries?
a. large total surface area
b. small individual diameter
c. thin walls
d. high blood velocity
e. highly branched
5. Which of the following would
not
result in tissue edema?
a. an increase in the concentration of plasma proteins
b. an increase in the pore size of systemic capillaries
c. an increase in venous pressure
d. blockage of lymph vessels
e. a decrease in the protein concentration of the plasma
6. Which statement comparing the systemic and pulmonary
circuits is
true?
a. The blood fl ow is greater through the systemic.
b. The blood fl ow is greater through the pulmonary.
c. The absolute pressure is higher in the pulmonary.
d. The blood fl ow is the same in both.
e. The pressure gradient is the same in both.
7. What is mainly responsible for the delay between the atrial and
ventricular contractions?
a. the shallow slope of AV node pacemaker potentials
b. slow action potential conduction velocity of AV node cells
c. slow action potential conduction velocity along atrial muscle
cell membranes
d. slow action potential conduction in the Purkinje network of
the ventricles
e. greater parasympathetic nerve fi ring to the ventricles than to
the atria
8. Which of the pressures below is closest to the mean arterial
blood pressure in a person whose systolic blood pressure is
135 mmHg and pulse pressure is 50 mmHg?
a. 110 mmHg
b. 78 mmHg
c. 102 mmHg
d. 152 mmHg
e. 85 mmHg
9. Which of the following would help restore homeostasis in the
fi rst few moments after a person’s mean arterial pressure became
elevated?
a. a decrease in baroreceptor action potential frequency
b. a decrease in action potential frequency along
parasympathetic neurons to the heart
c. an increase in action potential along sympathetic neurons to
the heart
d. a decrease in action potential frequency along sympathetic
neurons to arterioles
e. an increase in total peripheral resistance
10. Which is
false
about L-type calcium channels in cardiac
ventricular muscle cells?
a. They are open during the plateau of the action potential.
b. They allow calcium entry that triggers sarcoplasmic
reticulum calcium release.
c. They are found in the T-tubule membrane.
d. They open in response to depolarization of the membrane.
e. They contribute to the pacemaker potential.
11. Which correctly pairs an ECG phase with the cardiac event
responsible?
a. P-wave: Depolarization of the ventricles
b. P-wave: Depolarization of the AV node
c. QRS-wave: Depolarization of the ventricles
d. QRS-wave: Repolarization of the ventricles
e. T-wave: Repolarization of the atria
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