Florida International University

BIO PCB 4023

Chapter 14

1)Which of the following equations correctly relates flow, pressure, and resistance?

1. 1. resistance = flow × pressure
   2. pressure = flow × resistance
   3. flow = pressure × resistance
   4. flow = pressure - resistance
   5. flow = pressure + resistance
2. What is the driving force for blood flow through the systemic circuit?
   1. mean arterial pressure
   2. left ventricular pressure
   3. central venous pressure
   4. right atrial pressure
   5. capillary hydrostatic pressure
3. In comparison to the systemic circuit, the pulmonary circuit
   1. has an equal pressure gradient to drive blood flow.
   2. has lower blood flow.
   3. is under greater pressure.
   4. transports deoxygenated blood.
   5. has lower resistance to blood flow.
4. Which of the following would increase the rate of blood flow through a blood vessel?
   1. increased pressure of the blood entering the vessel
   2. increased viscosity of the blood
   3. constriction of the blood vessel
   4. decreased radius of the vessel
   5. increased length of the vessel
5. Which of the following equations is correct?
   1. resistance = (length × radius4) / viscosity
   2. mean arterial pressure = cardiac output × stroke volume
   3. cardiac output = mean arterial pressure × total peripheral resistance
   4. cardiac output = stroke volume × heart rate
   5. mean arterial pressure = resistance × viscosity
6. Which of the following is NOT a component of the microcirculation?
   1. veins
   2. arterioles
   3. metarterioles
   4. capillaries
   5. venules  1
7. The lumen of every blood vessel is lined by a monolayer of what cell type?
   1. fibroblasts
   2. erythrocytes
   3. smooth muscle cells
   4. endothelial cells
   5. platelets
8. What is/are the component(s) of a blood vessel's extracellular matrix that provide(s) the tensile strength required to withstand pressure?
   1. albumin
   2. elastin

8. 3. hemoglobin
   4. gap junctions
   5. collagen
9. The elastic nature of the largest blood vessel's walls allows them to act as a    , maintaining the driving force for blood flow while the heart is relaxed during diastole.
   1. contractile force
   2. non-compliant structure
   3. pressure reservoir
   4. non-distensible structure
   5. volume reservoir
10. The blood vessels of largest diameter are the    , and the blood vessels with the thickest walls are the

             .

10. 1. arteries : arterioles
    2. arteries : veins
    3. arteries : arteries
    4. veins : arteries
    5. veins : veins
11. What component of artery walls allows them to store energy that is later used to maintain continuous blood flow through the circulatory system?
    1. elastin
    2. skeletal muscle
    3. smooth muscle
    4. endothelium
    5. collagen
12. Arteries have           compliance and          resistance to flow.
    1. low : low B) high : high C) zero : high D) high : low E) low : high

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13. What is a measure of the change in vascular volume as pressure within the vessel is altered?
    1. blood flow
    2. compliance
    3. resistance
    4. the pressure gradient
    5. diffusibility
14. A person goes to the doctor and is told his blood pressure is 90/60 and his pulse is 80. Which of the following is FALSE?
    1. Pulse pressure is 80 mm Hg.
    2. Heart rate is 80.
    3. Diastolic pressure is 60.
    4. Systolic pressure is 90 mm Hg.
    5. Mean arterial pressure is 70 mm Hg.
15. Blood pressure is usually estimated from indirect measurements of the pressure in what structure?
    1. brachial artery
    2. radial artery
    3. left ventricle
    4. femoral artery
    5. aorta
16. Resistance to blood flow is regulated primarily by what blood vessels?
    1. capillaries B) arterioles C) veins D) ventricle E) arteries

17. In the circulatory system, the largest pressure drop occurs across which blood vessels?
    1. arterioles B) arteries C) veins D) venules E) capillaries
18. The pulsatile nature of blood pressure is greatest in which blood vessels?
    1. arteries B) capillaries C) arterioles D) venules E) veins
19. The total cross-sectional area is greatest in which blood vessels?
    1. capillaries B) veins C) venules D) arteries E) arterioles
20. The contractile activity of smooth muscle cells within which type of blood vessel is primarily involved in the control of the organ blood flow and mean arterial pressure?
    1. arteries B) veins C) capillaries D) venules E) arterioles

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21. Blood flow velocity is inversely proportional to the pooled surface area of a structure; therefore, it is greatest in the                                      and slowest in the     .
    1. arterioles : veins
    2. arteries : capillaries
    3. capillaries : arteries
    4. arteries : veins
    5. veins : arteries
22. Which of the following statements about smooth muscle in arterioles is FALSE?
    1. The muscle is multi-unit smooth muscle.
    2. Muscle contraction is under intrinsic controls.
    3. The muscle forms rings around the arteriole.
    4. The muscle has inherent (myogenic) tone.
    5. Muscle contraction is under extrinsic controls.
23. What is the purpose of extrinsic control of arteriolar smooth muscle contractile activity?
    1. regulate blood flow through specific capillary beds
    2. regulate heart rate
    3. regulate cardiac output
    4. regulate stroke volume
    5. regulate mean arterial pressure
24. Which of the following chemicals' concentration is NOT increased by an elevation in metabolic activity?
    1. potassium
    2. pyruvic acid
    3. carbon dioxide
    4. hydrogen
    5. oxygen
25. Chemicals released by metabolically active cells will cause which of the following?
    1. contraction of arteriolar smooth muscle to decrease blood flow
    2. contraction of capillary smooth muscle to increase blood flow
    3. relaxation of capillary smooth muscle to decrease blood flow
    4. contraction of arteriolar smooth muscle to increase blood flow
    5. relaxation of arteriolar smooth muscle to increase blood flow
26. What is a decrease in tissue oxygen called?
    1. hyperoxia B) ischemia C) hypoxemia D) hyperemia E) hypoxia

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27. What is an increase in blood flow in response to an increase in tissue metabolic activity called?

27. 1. hypoxia
    2. hyperoxia
    3. reactive hyperemia
    4. active hyperemia
    5. ischemia
28. In response to a decrease in tissue metabolic activity, tissue oxygen concentrations   , which causes a(n)             .
    1. decrease : active hyperemic response
    2. decrease : increase in tissue ischemia
    3. increase : constriction of the arterioles
    4. decrease : dilation of the arterioles
    5. increase : active hyperemic response
29. A decrease in pressure within an arteriole will initiate a(n)
    1. cardiac and venous baroreceptor reflex.
    2. arterial baroreceptor reflex.
    3. myogenic response.
    4. sinus arrhythmia.
    5. active hyperemia.
30. Which of the following accurately compares active hyperemia to reactive hyperemia?
    1. One is an increase in blood flow, the other is a decrease.
    2. One is caused by increased metabolic activity, the other in response to an increase in metabolites from an occlusion to blood flow.
    3. One is caused by an increase in metabolites, the other to a decrease in perfusion pressure.
    4. One involves vasodilation, the other vasoconstriction.
    5. One is an intrinsic response, the other an extrinsic response.
31. An increase in the concentration of which of the following within the interstitial space surrounding an arteriole would cause that vessel to constrict?
    1. lactic acid
    2. prostacyclin
    3. nitric oxide
    4. adenosine
    5. oxygen
32. Which of the following substances is secreted by endothelial cells and causes vasoconstriction?
    1. adenosine
    2. oxygen
    3. bradykinin
    4. nitric oxide
    5. endothelin-1

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33. Which of the following substances is continuously secreted by endothelial cells and causes vasodilation?
    1. endothelin-1
    2. bradykinin
    3. nitric oxide
    4. adenosine
    5. oxygen
34. Which of the following is an important vasodilator in coronary arteries?
    1. oxygen
    2. endothelin-1
    3. bradykinin

34. 4. adenosine
    5. nitric oxide
35. During exercise, which organs receive an increase in the proportion of cardiac output delivered to them?
    1. gastrointestinal tract and skeletal muscle
    2. skeletal muscle, heart, and brain
    3. brain and heart
    4. skeletal muscle, heart, and skin
    5. skeletal muscle, skin, and brain
36. Any change in the relative distribution of cardiac output to an organ is typically due to changes in which of the following?
    1. mean arterial pressure
    2. viscosity of the blood moving through that organ's vascular bed
    3. resistance of that organ's vascular bed
    4. central venous pressure
    5. compliance of that organ's vascular bed
37. During exercise, which of the following tissues receive less blood flow compared to resting conditions?
    1. gastrointestinal tract only
    2. brain only
    3. skin only
    4. heart only
    5. both gastrointestinal tract and skin
38. Which of the following would decrease mean arterial pressure?
    1. increase in stroke volume
    2. increase in venous return
    3. increase in heart rate
    4. increase in total peripheral resistance
    5. increase in arteriole diameter

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39. What type of adrenergic receptor is found in the smooth muscle of most systemic arterioles?
    1. alpha only
    2. beta1 only
    3. beta2 only
    4. beta3 only
    5. both alpha and beta1
40. The effects of epinephrine on vascular resistance are dependent upon which of the following?
    1. concentration of local metabolites
    2. relative distribution of nicotinic and muscarinic receptors
    3. relative distribution of alpha and beta receptors
    4. direction of change in mean arterial pressure
    5. specific baroreceptor activated (low or high pressure)
41. In cardiac and skeletal muscle vasculature, the distribution of alpha and beta receptors is such that epinephrine will
    1. induce a dilation that increases blood flow to these tissues.
    2. have no effect on peripheral resistance.
    3. increase skeletal muscle contractility.
    4. induce a constriction that decreases blood flow to these tissues.
    5. increase myocardial contractility.
42. Arteriolar smooth muscle in which of the following tissues tends to have beta2 receptors predominating?

42. 1. gastrointestinal tract
    2. liver
    3. skeletal muscle
    4. skin
    5. brain
43. Drugs that block angiotensin-converting enzyme would cause which of the following?
    1. decrease in epinephrine release
    2. activation of the parasympathetic nervous system
    3. stimulation of reactive hyperemia
    4. decreased mean arterial pressure
    5. decreased heart rate
44. Fenestrated capillaries are unique in their ability to
    1. maintain a low permeability to small water-soluble molecules.
    2. restrict the passage of proteins across endothelial cells.
    3. move molecules across endothelial cells by transcytosis.
    4. allow relatively large molecules to pass between endothelial cells.
    5. allow few molecules to pass between endothelial cells.

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45. What organ has capillaries that are the most restrictive to movement of hydrophilic solutes?
    1. liver
    2. kidneys
    3. skeletal muscle
    4. bone marrow
    5. brain
46. Which of the following would increase blood flow through a capillary bed?
    1. constriction of the arteriole leading into the capillary bed
    2. increase in venous pressure
    3. contraction of precapillary sphincters in the capillary bed
    4. contraction of smooth muscle in the metarterioles bypassing the capillary bed
    5. decrease in blood pressure in the arteriole leading into the capillary bed
47. Which of the following would cause relaxation of precapillary sphincters?
    1. parasympathetic activity
    2. epinephrine
    3. vasopressin
    4. sympathetic activity
    5. carbon dioxide
48. Glucose moves across continuous capillary walls by what mechanism?
    1. secondary active transport
    2. facilitated
    3. transcytosis
    4. diffusion
    5. primary active transport
49. Which of the following is NOT a mechanism that enables molecules to move across capillary endothelial cells?
    1. movement through water-filled gaps between endothelial cells
    2. rapid diffusion of water-soluble molecules directly across the endothelial cells
    3. transcytosis across endothelial cells
    4. movement of exchangeable proteins across endothelial cells
    5. diffusion of lipid-soluble molecules directly across the endothelial cell

50.               describes the movement of fluid out of the capillary, while    describes the movement of fluid into the capillary.
    1. Filtration : absorption
    2. Edema : venous pooling
    3. Absorption : filtration
    4. Hydrostatic pressure : oncotic pressure
    5. Venous pooling : edema

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51. The portion of osmotic pressure exerted by  in the blood is known as colloid osmotic pressure (or oncotic pressure).
    1. small ions B) lipids C) steroids D) large ions E) proteins
52. Under normal conditions, which Starling forces favor filtration?
    1. capillary hydrostatic pressure and interstitial fluid hydrostatic pressure
    2. capillary hydrostatic pressure and interstitial fluid osmotic pressure
    3. capillary hydrostatic pressure and plasma oncotic pressure
    4. interstitial fluid hydrostatic pressure and interstitial fluid osmotic pressure
    5. interstitial fluid hydrostatic pressure and plasma oncotic pressure
53. Which of the following inaccurately represents normal forces across capillary walls?
    1. Interstitial fluid oncotic pressure is almost zero.
    2. At rest, net filtration occurs across capillary walls.
    3. Capillary hydrostatic pressure decreases from arteriole end to venous end.
    4. Capillary oncotic pressure is due primarily to plasma proteins.
    5. Interstitial fluid hydrostatic pressure increases from arteriole end to venous end.
54. Given that the net filtration of fluid out of the capillaries averages about 3 liters per day, how is blood volume maintained in light of this apparent fluid loss?
    1. The kidneys are involved in the reabsorption of the remaining fluid.
    2. Gravity moves the fluid to the lowest point in the body, where the fluid is absorbed.
    3. While fluid moves out across the capillary, it tends to move inward across veins.
    4. The lymphatic system returns filtered fluid to the blood.
    5. The net filtration is equally balanced by absorption.
55. Which of the following is NOT a mechanism that alters the balance between filtration and absorption in the body?
    1. increasing the elimination of plasma proteins in cases of kidney damage
    2. increasing the permeability of the capillaries in regions of tissue damage
    3. increasing capillary hydrostatic pressure within the feet as one stands
    4. increasing hydrostatic pressure gradient in cases of enhanced interstitial protein
    5. decreasing plasma protein synthesis in cases of liver damage
56. Which of the following comparisons between systemic capillaries and lymphatic capillaries is TRUE?
    1. Pressure is higher in lymphatic capillaries.
    2. Blood cells are found in both types of capillaries.
    3. Fluid enters systemic capillaries from systemic arterioles; fluid enters lymphatic capillaries from lymphatic veins.
    4. Walls of systemic capillaries are more permeable.
    5. Net filtration occurs across systemic capillaries; net absorption occurs across lymphatic capillaries.

57. Foreign materials are filtered out of the lymphatic fluid by what type of cell located within the lymph nodes?
    1. erythrocytes
    2. platelets

57. 3. mast cells
    4. macrophages
    5. leukocytes
58. Exchange between blood and interstitial fluid occurs across capillaries and, to a lesser extent,
    1. arterioles.
    2. veins.
    3. arteries.
    4. venules.
    5. metarterioles.
59. What region of the cardiovascular system contains valves?
    1. heart only
    2. metarterioles only
    3. veins only
    4. both the heart and veins
    5. the heart, metarterioles, and veins
60. Veins functions as          reservoirs due to their        compliance.
    1. pressure : lack of
    2. volume : low
    3. pressure : low
    4. pressure : high
    5. volume : high
61. Valves, which are found        , maintain the unidirectional movement of blood, thereby facilitating the return of blood to the heart.
    1. only in peripheral veins
    2. in all venules
    3. only in arteries
    4. only in central veins
    5. in all veins
62. The high compliance of veins allows them to
    1. provide the driving force for the movement of blood through the vasculature during diastole.
    2. rapidly change central venous pressure with small changes in blood volume.
    3. act as pressure reservoirs.
    4. hold only small volumes of blood.
    5. accommodate large volumes of blood with little change in pressure.

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63. At rest, the greatest proportion of blood volume is present within the
    1. systemic capillaries.
    2. systemic arteries.
    3. systemic veins.
    4. pulmonary veins.
    5. heart.
64. Which of the following would decrease central venous pressure?
    1. activity of skeletal muscles
    2. increased respiratory activity
    3. increased sympathetic activity
    4. standing up
    5. increased blood volume
65. An increase in the volume of blood ejected from the heart, with no change in total peripheral resistance,

would

65. 1. elevate central venous pressure.
    2. reduce the stretch on the aorta.
    3. elevate pulmonary venous pressure.
    4. reduce mean arterial pressure.
    5. elevate mean arterial pressure.
66. An increase in total peripheral resistance, in the absence of any change in cardiac output, would
    1. elevate mean arterial pressure.
    2. reduce the stretch on the aorta.
    3. reduce mean arterial pressure.
    4. decrease central venous pressure.
    5. decrease pulmonary venous pressure.
67. The respiratory pump facilitates the return of blood to the heart by
    1. squeezing blood from the rhythmic contraction of the diaphragm muscle.
    2. decreasing the pressure gradient between abdominal and thoracic veins during expiration.
    3. raising the pressure gradient between abdominal and thoracic veins during inspiration.
    4. decreasing the pressure gradient between abdominal and thoracic veins during inspiration.
    5. raising the pressure gradient between abdominal and thoracic veins during expiration.
68. Which of the following would NOT increase mean arterial pressure?
    1. decreased parasympathetic activity effects on the heart
    2. increased sympathetic activity to the veins
    3. increased sympathetic activity to the heart
    4. decreased parasympathetic activity effects on the arterioles
    5. increased levels of epinephrine in the blood

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69. The long-term regulation of arterial blood pressure involves the
    1. stimulation of an increase in urine flow through the kidneys.
    2. control of peripheral resistance.
    3. immediate change in activity of the nervous system.
    4. control of blood volume by the kidneys.
    5. release of hormones over a period of minutes.
70.               are responsible for the detection of mean arterial pressure.
    1. Aortic chemoreceptors
    2. Medullary chemoreceptors
    3. Venous baroreceptors
    4. Thermoreceptors
    5. Arterial baroreceptors
71. Which of the following best classifies the baroreceptor reflex?
    1. cranial; autonomic; conditioned; monosynaptic
    2. cranial; autonomic; innate; polysynaptic
    3. cranial; somatic; conditioned; polysynaptic
    4. spinal; autonomic; innate; polysynaptic
    5. spinal; autonomic; innate; monosynaptic
72. As mean arterial pressure increases, the , informing the medulla oblongata that blood pressure has indeed increased.
    1. number of neurons stimulated within the aortic arch increases
    2. blood flow to the brain increases
    3. number of sympathetic neurons activated decreases
    4. amplitude of the action potentials from the baroreceptors increases

72. 5. frequency of action potentials from the baroreceptors increases
73. Information about mean arterial pressure is integrated within what area of the central nervous system?
    1. cerebellum
    2. pons
    3. medulla oblongata
    4. cervical spinal cord
    5. hypothalamus
74. Where is the cardiovascular control center?
    1. adrenal medulla
    2. medulla oblongata
    3. hypothalamus
    4. adrenal cortex
    5. pons  12
75. Which of the following descriptions of the autonomic innervation of the cardiovascular system is FALSE?
    1. Only sympathetic neurons provide significant innervation of the contractile cells of the heart.
    2. Only sympathetic neurons innervate smooth muscle in veins.
    3. Both sympathetic and parasympathetic neurons innervate smooth muscle in arterioles.
    4. Both sympathetic and parasympathetic neurons innervate the SA node.
    5. Sympathetic activity increases cardiac output, whereas parasympathetic activity decreases cardiac output.

76. Which of the following will NOT occur in response to a decrease in the extent of stretch detected by a baroreceptor?
    1. increased heart rate
    2. increased urine flow
    3. increased ventricular contractility
    4. increased venomotor tone
    5. increased peripheral resistance
77. Which of the following is NOT altered within seconds to minutes of the baroreceptor reflex being activated?
    1. venomotor tone
    2. total peripheral resistance
    3. heart rate
    4. stroke volume
    5. blood volume
78. Which of the following does NOT occur in response to baroreceptors detecting an increase in mean arterial pressure?
    1. decreased end-diastolic volume
    2. decreased frequency of sinoatrial node action potentials
    3. decreased venous compliance
    4. vasoconstriction
    5. decreased heart rate
79. The chronic elevation in arterial pressure (hypertension) that occurs in many individuals results in
    1. the resetting of the baroreceptor to a lower pressure.
    2. a decreased sensitivity of the baroreceptor that causes pressure to fluctuate.
    3. the maintenance of a constant error signal by the baroreceptor.
    4. the baroreceptors becoming more sensitive to pressure.
    5. a gradual increase in pressure that resets the baroreceptors.

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80. The reduction in organ blood flow that results from a decrease in mean arterial pressure would be exacerbated by the            that occurs as a consequence of the baroreceptor reflex.
    1. increased venous return
    2. increased peripheral resistance
    3. increased ventricular contractility
    4. decreased compliance of the veins
    5. increased stroke volume
81. An increase in sympathetic nervous activity to arterioles will have little effect on vasoconstriction of the
    1. brain and heart.
    2. skeletal muscles.
    3. kidneys.
    4. gastrointestinal tract.
    5. heart and kidneys.
82. The hormone vasopressin acts in the short term to                                            and in the long term to                                                                          , thereby increasing mean arterial pressure.
    1. vasoconstrict arterioles : decrease urine outflow
    2. increase urine outflow : vasodilate arterioles
    3. vasodilate arterioles : increase urine outflow
    4. vasodilate arterioles : decrease urine outflow
    5. decrease urine outflow : vasoconstrict arterioles
83. Due to their location, baroreceptors in the large systemic veins and the heart function primarily to monitor
    1. heart rate.
    2. mean arterial pressure.
    3. blood flow.
    4. blood volume.
    5. total peripheral resistance.
84. Which of the following terms is used to label the rhythmic changes in sympathetic and parasympathetic activity that affect heart rate coincident with respiration?
    1. pulmonary sinus rhythmia
    2. respiratory sinus rhythmia
    3. lung sinus rhythmia
    4. respiratory sinus arrhythmia
    5. pulmonary sinus arrhythmia

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85. Despite seeming counterproductive, an increase in arterial carbon dioxide levels activates   , which causes a(n)            in heart rate and a(n)        in total peripheral resistance.
    1. baroreceptors : decrease : decrease
    2. baroreceptors : increase : increase
    3. chemoreceptors : decrease : increase
    4. chemoreceptors: decrease : decrease
    5. baroreceptors : decrease : increase
86. Which of the following will NOT occur as a consequence of the activation of the baroreceptor reflex that would occur in response to an increased heat load within the body?
    1. an increase in resistance within the skin vasculature
    2. an increase in stroke volume
    3. an increase in heart rate
    4. an increase in venoconstriction
    5. a decrease in resistance within the skeletal muscle vasculature
87. The increase in stroke volume that occurs during exercise is caused primarily by a(n)

87. 1. increase in end-diastolic volume.
    2. increase in myocardial contractility.
    3. decrease in peripheral resistance.
    4. increase in venous return.
    5. decrease in end-systolic volume.
88. The increase in blood flow to active skeletal muscle relative to other organs is largely caused by the
    1. increase in local metabolic factors within the muscle.
    2. increase in sympathetic activity.
    3. decrease in metabolic factors within the muscle.
    4. decrease in parasympathetic activity.
    5. increase in parasympathetic activity.
89. Which of the following accurately describes sympathetic control of blood vessels in the skin during thermoregulation?
    1. Heat causes an increase in sympathetic activity, resulting in vasodilation.
    2. Heat causes a decrease in sympathetic activity, resulting in vasoconstriction.
    3. Heat activates the parasympathetic activity and has no effect on the sympathetic nervous system.
    4. Heat causes a decrease in sympathetic activity, resulting in vasodilation.
    5. Heat causes an increase in sympathetic activity, resulting in vasoconstriction.
90. Mean arterial pressure can be increased by all of the following EXCEPT
    1. increasing venous return.
    2. increasing blood volume.
    3. decreasing end-diastolic volume.
    4. increasing sympathetic activity.
    5. increasing heart rate.

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91. Which of the following can cause vasoconstriction?
    1. angiotensin II
    2. increase in carbon dioxide
    3. release of nitric oxide
    4. increase in histamine
    5. increase in osmolarity
92. The primary mechanism for exchange of substances across the capillary wall is
    1. diffusion.
    2. mediated transport.
    3. bulk flow.
    4. vesicle transport.
    5. active transport.
93. Given the following information, calculate the net filtration pressure: capillary hydrostatic pressure = 30 mm Hg; interstitial fluid hydrostatic pressure = 5 mm Hg; capillary oncotic pressure = 25 mm Hg; and interstitial fluid oncotic pressure = 10 mm Hg.
    1. 0 mm Hg, no net force
    2. 40 mm Hg, favoring filtration
    3. 10 mm Hg, favoring filtration
    4. -10 mm Hg, favoring reabsorption
    5. -40 mm Hg, favoring reabsorption
94. Which of the following can cause edema?
    1. decreased venous pressure only
    2. damage to capillary walls only
    3. increase in extravasated plasma proteins only

94. 4. both an increase in plasma proteins and a decrease in venous pressure
    5. both damage to capillary walls and an increase in extravasated plasma proteins
95. Which of the following is an incorrect description of a blood vessel type?
    1. The radius of arterioles can be regulated by both intrinsic and extrinsic controls.
    2. Most of the blood volume at rest is in the systemic veins.
    3. Arteries are elastic.
    4. Capillary walls are comprised of only two cell layers, minimizing the distance for exchange.
    5. Veins have high compliance.
96. During exercise, carbon dioxide produced by muscle cells causes vasodilation in skeletal muscle. This is an example of
    1. active hyperemia.
    2. flow autoregulation.
    3. ischemia.
    4. reactive hyperemia.
    5. hypoxia.  16
97. Which of the following structures contains high pressure baroreceptors?
    1. aortic arch only
    2. carotid sinus only
    3. right atrium only
    4. both the aortic arch and carotid sinus
    5. aortic arch, right atrium, and carotid sinus
98. Of the following choices, which has the elastic recoil of its walls during diastole, causing a continuation of blood flow throughout the cardiac cycle?
    1. capillary B) arteriole C) vein D) venule E) artery
99. Which of the following has high compliance, allowing it to hold a large volume of blood with little change in pressure?
    1. capillary B) vein C) artery D) arteriole E) venule
100. Which of the following has the regulation of its radius determining blood flow through specific organs?

A) capillary B) venule C) artery D) vein E) arteriole

101. Which of the following is the smallest of blood vessels with thin walls allowing for ready exchange of material between blood and tissue?

A) vein B) artery C) arteriole D) capillary E) venule

102. Which of the following blood vessels is slightly larger than capillaries, allowing for some exchange between blood and the tissue?

A) venule B) artery C) vein D) capillary E) arteriole

103. Which of the following is a decrease in tissue oxygen?

1. ischemia
2. reactive hyperemia
3. myogenic response
4. hypoxia
5. active hyperemia

104. Which of the following is a decrease in blood supply to the tissue such that it does not meet the metabolic demands of the tissue?

1. myogenic response
2. hypoxia

3. ischemia
4. reactive hyperemia
5. active hyperemia

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105. An increase in blood flow to tissues in response to increased metabolic activity is called

1. ischemia.
2. myogenic response.
3. reactive hyperemia.
4. hypoxia.
5. active hyperemia.

106. A constriction of an arteriole in response to stretch of the arteriole smooth muscle is called

1. myogenic response.
2. reactive hyperemia.
3. ischemia.
4. active hyperemia.
5. hypoxia.

107. An increase in blood flow to tissues in response to a previous reduction in blood flow is called

1. hypoxia.
2. reactive hyperemia.
3. active hyperemia.
4. ischemia.
5. myogenic response.

108. Vasopressin has what effect on systemic arterioles?

1. vasospasm
2. vasoconstriction and vasospasm
3. vasodilation
4. neither vasodilation or vasoconstriction, but may cause vasospasm
5. vasoconstriction

109. Oxygen has what effect on systemic arterioles?

1. vasodilation
2. vasoconstriction and vasospasm
3. vasospasm
4. vasoconstriction
5. neither vasodilation or vasoconstriction, but may cause vasospasm

110. Angiotensin II has what effect on systemic arterioles?

1. vasoconstriction
2. vasospasm
3. vasoconstriction and vasospasm
4. neither vasodilation or vasoconstriction, but may cause vasospasm
5. vasodilation

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111. Carbon dioxide has what effect on systemic arterioles?

1. vasoconstriction
2. neither vasodilation or vasoconstriction, but may cause vasospasm
3. vasodilation
4. vasoconstriction and vasospasm
5. vasospasm

112. Nitric oxide has what effect on systemic arterioles?

1. vasodilation
2. neither vasodilation or vasoconstriction, but may cause vasospasm
3. vasoconstriction
4. vasospasm
5. vasoconstriction and vasospasm

113. Hydrogen ions have what effect on systemic arterioles?

1. vasoconstriction
2. vasospasm
3. vasodilation
4. vasoconstriction and vasospasm
5. neither vasodilation or vasoconstriction, but may cause vasospasm

114. Sympathetic nerves have what effect on systemic arterioles?

1. neither vasodilation or vasoconstriction, but may cause vasospasm
2. vasodilation
3. vasoconstriction
4. vasospasm
5. vasoconstriction and vasospasm

115. Parasympathetic nervous activity has what effect on systemic arterioles?

1. vasoconstriction
2. neither vasodilation or vasoconstriction, but may cause vasospasm
3. vasospasm
4. vasodilation
5. neither vasoconstriction and vasodilation

116. What is the equation relating flow to resistance and a pressure gradient?

1. flow = pressure gradient / resistance
2. flow × resistance = pressure × gradient
3. flow/resistance = 1/pressure gradient
4. flow = pressure × resistance
5. flow × resistance = 1/pressure gradient

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117. What is the driving force for blood flow through the systemic circuit?

1. mean arterial pressure
2. total peripheral resistance
3. perfusion pressure
4. pulse pressure
5. cardiac output

118. What is a decrease in blood flow that is less than what is necessary to keep up with metabolic demands called?

A) hypoxia B) hypoxemia C) infarction D) hyperemia E) ischemia

119. What are local controls that tend to keep blood flow constant called?

1. osteogenic factors
2. flow autoregulation
3. flow telemetry
4. autonomics
5. extrinsic factors

120. Bradykinin causes vasodilation by stimulating the release of what substance from endothelial cells?

1. thromboxane A2
2. nitric oxide

3. cyclooxygenase
4. endothelin I
5. arachidonic acid

121. Epinephrine triggers vasodilation by binding to which receptors and vasoconstriction by binding to which receptors?

1. beta2 : alpha
2. alpha2 : beta2
3. alpha1 : beta1
4. beta : cholinergic
5. alpha : beta2

122. To produce angiotensin II, what must be secreted from the kidney to convert angiotensinogen to angiotensin I, which is then converted to angiotensin II by angiotensin converting enzyme?

1. preangiotensin
2. renin
3. erythropoietin
4. vitamin D3
5. angiotensinogen

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123. What are blood vessels that normally bypass capillary beds are called?

1. A-V malformations
2. pararterioles
3. venules
4. pre-capillary sphincters
5. metarterioles.

124. What is bulk flow of fluid from inside a capillary into interstitial fluid called?

A) adsorption B) absorption C) secretion D) filtration E) excretion

125. What is the fluid within the lymphatic vessels called?

A) plasma B) filtrate C) lymph D) pus E) exudates

126. What is a drop in mean arterial pressure that results from standing up called?

1. recumbent hypotension
2. metastatic hypotension
3. paroxysmal hypotension
4. resultant hypotension
5. orthostatic hypotension

127. Smooth muscle in the veins has what type of adrenergic receptor?

1. alpha
2. gamma
3. alpha cholinergic
4. cholinergic
5. beta2

128. Which of the following is the equation relating cardiac output, mean arterial pressure, and total peripheral resistance?

1. MAP = CO - TPR
2. TPR = CO/MAP
3. MAP + CO + TPR = pulse pressure
4. CO = TPR/MAP
5. MAP = CO × TPR

129. Where are the arterial baroreceptors located?

1. coronary arteries
2. the pons
3. aortic arch and carotid sinuses (carotid arteries)
4. coronary sinuses and aortic arch
5. brachiocephalic artery

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130. What are the two functions of increasing blood flow to the skin during exercise?

1. facilitate dissipation of heat; remove water for sweat production
2. facilitate dissipation of heat; energy reserve for underlying musculature
3. fat utilization for energy production; remove water for sweat production
4. facilitate dissipation of heat; provide energy for sweat production
5. energy reserve for underlying musculature; provide energy for sweat production

131. In response to a decrease in the stretch of a baroreceptor, sympathetic nervous activity will       while parasympathetic nervous activity will                                                                  .

1. not change : remain constant
2. increase : decrease
3. decrease : remain constant
4. not change : increase
5. decrease : increase

132. An increase in the stretch of a baroreceptor will cause venomotor tone to    while ventricular contractility will          .

1. decrease : decrease
2. remain constant : not change
3. increase : not change
4. increase : increase
5. increase : decrease

133. What structures of the cardiovascular system are innervated by the sympathetic nervous system, but are NOT by the parasympathetic nervous system?

1. arteriolar smooth muscle and venous smooth muscle
2. SA node, AV node, and bundle of His
3. ventricular myocardium, arteriolar smooth muscle and venous smooth muscle
4. SA node and AV node
5. arteriolar smooth muscle

134. Calculate the net filtration pressure given the following information: capillary blood pressure = 40 mm Hg; interstitial fluid hydrostatic pressure = 2 mm Hg; plasma osmotic pressure = 20 mm Hg; and interstitial fluid osmotic pressure = 5 mm Hg. Does filtration or absorption occur across this capillary wall?

1. 67 mm Hg; absorption
2. 23 mm Hg; filtration
3. 27 mm Hg; filtration
4. 17 mm Hg; filtration
5. 27 mm Hg; absorption

135. Blood flowing through a vessel is subject to the same physical limitations as fluid flowing through a tube. Describe the physical properties of blood flow and blood pressure.
136. At this point, a number of equations in the text have expanded upon cardiac output = heart rate × stroke volume. These include equations for calculating blood flow, cardiac output (using variables other than those above), mean arterial pressure, and organ blood flow. Provide the equations for the above variables and briefly discuss their relevance.
137. While the basic constituents of blood vessels are similar across all vessel types, the proportion of each constituent is quite different. Describe the structure of each class of blood vessel, including the functional significance of that structure.
138. The smaller blood vessels, which include arterioles, capillaries, and venules, have unique functions. Identify the functions of each of the smaller blood vessels.

139. The regulation of mean arterial pressure involves the interaction between extrinsic and intrinsic mechanisms. While the intrinsic mechanisms can affect mean arterial pressure, they also play an important role in the distribution of cardiac output to individual organs. Discuss the role of the intrinsic mechanisms in the

control of organ resistance.

140. The processes of filtration and absorption across the endothelial cells of capillaries is driven by Starling's forces. List the components of Starling's forces and describe how those forces determine the absorption of water across capillaries, including a discussion of how those forces are altered by standing and tissue injury.
141. Mean arterial pressure is regulated by a negative feedback system that involves the central nervous system. Discuss the afferent limb, the efferent limb, and the integrator of the baroreceptor reflex.
142. The baroreceptors are responsible for detecting and responding to changes in mean arterial pressure. Follow the short-term and long-term responses of the baroreceptor reflex to an acute and chronic increase in mean arterial pressure.
143. As mean arterial pressure changes, both short- and long-term changes are initiated that can interact with one another. Describe how a chronic hypotensive state could become life threatening.
144. Both short- and long-term regulation of mean arterial pressure is mediated through the release of hormones.

Describe the hormones discussed in Chapter 14 that are involved in the regulation of mean arterial pressure and how they are able to stimulate an increase in mean arterial pressure.

145. Contraction of smooth muscle cells in arterioles causes (vasoconstriction / vasodilation).
146. Arteries are (elastic / compliant).