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1. If we were able to artificially alter the
membrane permeability of pacemaker cells so that sodium influx is more rapid:
a. heart rate would increase due to a
decreased time for depolarization of the pacemaker cells.
b. slow calcium channels in the pacemaker
tissue would be cycling at a greater rate.
c. heart rate would decrease, but blood
pressure would rise due to the excess sodium present.
d. tetanic contraction would occur due to
the short absolute refractory period of cardiac muscle.
2. The tricuspid valve is closed:
a. while the ventricle is in diastole.
b. when the ventricle is in systole.
c. while the atrium is contracting.
d. by the movement of blood from atrium
to ventricle.
4. The term for pain associated with
deficient blood delivery to the heart that may be caused by the transient spasm
of coronary arteries is:
a. ischemia.
b. pericarditis.
c. myocardial infarct.
d. angina pectoris.
5. The foramen ovale:
a. connects the two atria in the fetal
heart.
b. is a condition in which the heart
valves do not completely close.
c. is a shallow depression in the
interventricular septum.
d. is a connection between the pulmonary
trunk and the aorta in the fetus.
6. If a significant amount of connective
tissue were to develop connecting the visceral and parietal pericardial layers
together, which of the following would be a likely consequence?
a. interference with normal mechanical
cardiac activity
b. strengthening of the delicate
pericardial layers and an improvement of cardiac function
c. decreased production of fluid in the
pericardial cavity since it is no longer necessary
d. decreased friction between the
visceral and parietal layers
8. If cardiac muscle is deprived of its
normal blood supply, damage would primarily result from:
a. decreased delivery of oxygen.
b. a decrease in the number of available
mitochondria for energy production.
c. a lack of nutrients to feed into
metabolic pathways.
d. an inadequate supply of lactic acid.
9. The deflection waves in an ECG tracing
include:
a. the P wave, which is present only in
patients who have had a heart attack.
b. the Q-T interval, which indicates the
time of atrial contraction.
c. the PQRS complex, which follows
ventricular contraction.
d. the T wave, which indicates
ventricular repolarization.
10. Small muscle masses attached to the chordae
tendineae are the:
a. trabeculae carneae.
b. pectinate muscles.
c. papillary muscles.
d. venae cavae.
11. Select the correct statement about the
heart valves.
a. The mitral valve separates the right
atrium from the right ventricle.
b. The tricuspid valve divides the left
atrium from the left ventricle.
c. Semilunar valves control the flow of
blood into the heart.
d. The AV valves are supported by chordae
tendineae so that they do not blow back up into the atria during ventricular
contraction.
12. The stroke volume for a normal resting
heart is ________ ml/beat.
a. 30
b. 50
c. 70
d. 90
13. The effect of endurance-type athletic
training may be to lower the resting heart rate. This phenomenon:
a. is a sign of dangerous overexertion.
b. is caused by hypertrophy of the heart
muscle.
c. results in decreased cardiac output.
d. does not occur in aerobic training.
14. When the heart is beating at a rate of 75
times per minute, the duration of one cardiac cycle is ________ second(s).
a. 0.8
b. 1.0
c. 1.2
d. 1.8
15. Which vessel of the heart receives blood
during right ventricular systole?
a. venae cavae
b. pulmonary artery
c. aorta
d. pulmonary veins
16. During the period of ventricular filling:
a. pressure in the heart is at its peak.
b. blood flows passively through the
atria and the open AV valves.
c. the atria remain in diastole.
d. it is represented by the P wave on the
ECG.
17. The P wave of a normal electrocardiogram
indicates:
a. ventricular repolarization.
b. ventricular depolarization.
c. atrial repolarization.
d. atrial depolarization.
19. Which of the following is not part of the
conduction system of the heart?
a. AV node
b. bundle of His
c. AV valve
d. SA node
20. Isovolumetric contraction:
a. refers to the short period during
ventricular systole when the ventricles are completely closed chambers.
b. occurs while the AV valves are open.
c. occurs immediately after the semilunar
valves close.
d. occurs only in people with heart valve
defects.
21. The left ventricular wall of the heart is
thicker than the right wall in order to:
a. accommodate a greater volume of blood.
b. expand the thoracic cage during
diastole.
c. pump blood with greater pressure.
d. pump blood through a smaller valve.
22. Compared to skeletal muscle, cardiac
muscle:
a. has gap junctions that allow it to act
as a functional syncytium.
b. lacks striations.
c. has more nuclei per cell.
d. cells are larger than skeletal muscle
cells.
23. Hemorrhage with a large loss of blood
causes:
a. a lowering of blood pressure due to
change in cardiac output.
b. a rise in blood pressure due to change
in cardiac output.
c. no change in blood pressure but a
slower heart rate.
d. no change in blood pressure but a
change in respiration.
24. Cardiac output is about ________
L/min.
a. 7.27
b. 6.26
c. 5.25
d. 4.25
25. Stenosis of the mitral valve may
initially cause a pressure increase in the:
a. venae cavae.
b. left ventricle.
c. pulmonary circulation.
d. coronary circulation.
26. Cardiac muscle cells are like skeletal
muscle cells in that they:
a. have gap junctions.
b. have end walls.
c. have I and A bands.
d. have intercalated disks.
27. Normal heart sounds are caused by which of
the following events?
a. excitation of the SA node
b. closure of the heart valves
c. friction of blood against the chamber
walls
d. contraction of ventricular muscle
28. During contraction of heart muscle cells:
a. the action potential is initiated by
voltage-regulated slow calcium channels.
b. some calcium enters the cell from the
extracellular space and triggers the release of larger amounts of calcium from
intracellular stores.
c. the action potential is prevented from
spreading from cell to cell by gap junctions.
d. calcium is prevented from entering
cardiac fibers that have been stimulated.
29. The second heart sound is heard during
which phase of the cardiac cycle?
a. isovolumetric relaxation
b. isovolumetric contraction
c. ventricular ejection
d. ventricular filling
30. Commotio cordis is:
a. heart failure due to a mild electrical
shock.
b. heart failure due to a severe
electrical shock.
c. heart failure due to a relatively mild
blow to the chest.
d. heart failure due to a loss of blood.
31. Cardiac reserve:
a. is determined by your genes and not
subject to improvement.
b. is unrelated to health.
c. can be improved by regular exercise.
d. can be determined by auscultation.
32. Damage to the ________ is referred to
as heart block.
a. SA node
b. AV valves
c. AV bundle
d. AV node
36. If the length of the absolute refractory
period in cardiac muscle cells was the same as it is for skeletal muscle cells:
a. it would be much longer before cardiac
cells could respond to a second stimulation.
b. contractions would last as long as the
refractory period.
c. tetanic contractions might occur,
which would stop the heart's pumping action.
d. it would be less than 1-2 ms.
37. Blood enters which of these vessels during
ventricular systole?
a. aorta
b. pulmonary arteries
c. pulmonary vein
d. aorta and pulmonary arteries
38. When holding a dissected heart in your
hands, it is easy to orient the right and left side by:
a. tracing out where the vena cava enters
the heart.
b. noticing the thickness of the
ventricle walls.
c. locating the aorta.
d. finding the pulmonary semilunar
valves.
39. Which of the following factors does not
influence heart rate?
a. skin color
b. age
c. gender
d. body temperature
41. Cardiac muscle:
a. has fewer mitochondria than skeletal
muscle.
b. relies mostly on glycolysis for
energy.
c. has sarcomeres with A bands and I
bands.
d. can operate for long periods without
oxygen as long as lactic acid is present.
42. Which of the following is not an
age-related change affecting the heart?
a. atherosclerosis
b. decline in cardiac reserve
c. fibrosis of cardiac muscle
d. thinning of the valve flaps
44. If the vagal nerves to the heart were cut,
the result would be that:
a. the heart would stop, since the vagal
nerves trigger the heart to contract.
b. the heart rate would increase by about
25 beats per minute.
c. the AV node would become the pacemaker
of the heart.
d. parasympathetic stimulation would
increase, causing a decrease in heart rate.
48. Negative chronotropic factors are:
a. factors that decrease afterload.
b. factors that increase afterload.
c. factors that decrease heart rate.
d. factors that increase heart rate.
49. Select the correct statement about the
structure of the heart wall.
a. The fibrous skeleton forms the bulk of
the heart.
b. Connective tissue in the heart wall
aids in the conduction of the action potential.
c. The heart chambers are lined by the
endomysium.
d. The myocardium is the layer of the
heart that actually contracts.
52. Blood within the pulmonary veins returns to
the:
a. right atrium.
b. left atrium.
c. right ventricle.
d. left ventricle.
54. To auscultate the aortic semilunar valve,
you would place your stethoscope:
a. in the second intercostal space to the
right of the sternum.
b. in the second intercostal space to the
left of the sternum.
c. in the fifth intercostal space inferior
to the left nipple.
d. in the fifth right intercostal space.
56. Norepinephrine acts on heart muscle
cells by:
a. decreasing heart contractility.
b. causing a decrease in stroke volume.
c. blocking the action of calcium.
d. causing threshold to be reached more
quickly.
57. Select the correct statement about cardiac
output.
a. A slow heart rate increases end
diastolic volume, stroke volume, and force of contraction.
b. Decreased venous return will result in
increased end diastolic volume.
c. If a semilunar valve were partially
obstructed, the end systolic volume in the affected ventricle would be
decreased.
d. Stroke volume increases if end
diastolic volume decreases.
58. The pericardial cavity:
a. is another name for the chambers of
the heart.
b. is a space between the fibrous
pericardium and the serous pericardium.
c. is the region of the thoracic cavity
that contains the heart.
d. contains a lubricating fluid called
serous fluid.
59. Select the correct statement about the
function of myocardial cells.
a. The all-or-none law as applied to
cardiac muscle means that the entire heart contracts as a unit or it does not
contract at all.
b. Cardiac muscle cells are each
innervated by a sympathetic nerve ending so that the nervous system can
increase heart rate.
c. The refractory period in skeletal
muscle is much longer than that in cardiac muscle.
d. The influx of potassium ions from
extracellular sources is the initiating event in cardiac muscle contraction.
60. Blood is carried to capillaries in the
myocardium by way of:
a. the coronary sinus.
b. the fossa ovalis.
c. coronary arteries.
d. coronary veins.
61. Select the correct statement about factors
that influence blood pressure.
a. An increase in cardiac output corresponds
to a decrease in blood pressure, due to the increased delivery.
b. Systemic vasodilation would increase
blood pressure, due to diversion of blood to essential areas.
c. Excess protein production would
decrease blood pressure.
d. Excess red cell production would cause
a blood pressure increase.
62. Which of the following is likely during
vigorous exercise?
a. Blood will be diverted to the
digestive organs.
b. The skin will be cold and clammy.
c. Capillaries of the active muscles will
be engorged with blood.
d. Blood flow to the kidneys increases.
65. Which of the following is not one of the
three main factors influencing blood pressure?
a. cardiac output
b. peripheral resistance
c. emotional state
d. blood volume
66. Select the correct statement about the
movement of materials at the capillary level.
a. Oxygen diffuses up its concentration
gradient.
b. Chemical waste products follow the
same general path as oxygen.
c. Carbon dioxide moves from its
production site into the interstitial fluid.
d. If the osmotic pressure in the blood
vessels is relatively higher than that in the tissues, tissue edema will
result.
67. A thrombus (blood clot) in the first branch
of the arch of the aorta would affect the flow of blood to the:
a. left side of the head and neck.
b. myocardium of the heart.
c. left upper arm.
d. right side of the head and neck and
right upper arm.
69. The term ductus venosus refers to:
a. a fetal shunt that bypasses the lungs.
b. damage to the valves in the veins,
leading to varicose veins.
c. a condition of the aged in which the
arteries lose elasticity.
d. a special vessel that allows blood to
bypass the liver.
70. The arteries that directly feed into the
capillary beds are called:
a. muscular arteries.
b. elastic arteries.
c. arterioles.
d. venules.
71. Which of the following signs of hypovolemic
shock is a relatively late sign?
a. cold, clammy skin
b. increased heart rate
c. rapid, thready pulse
d. rapidly falling blood pressure
72. The velocity of blood flow:
a. is in direct proportion to the total
cross-sectional area of the blood vessels.
b. is slower in the arteries than
capillaries since they possess a relatively large diameter.
c. is slower in the veins than in the
capillaries since veins have a large diameter.
d. is slowest in the capillaries since
the total cross-sectional area is the greatest.
73. Factors that aid venous return include
all except:
a. activity of skeletal muscles.
b. pressure changes in the thorax.
c. venous valves.
d. urinary output.
75. Which of the following are involved
directly in pulmonary circulation?
a. superior vena cava, right atrium, and
left ventricle
b. right ventricle, pulmonary artery, and
left atrium
c. left ventricle, aorta, and inferior
vena cava
d. right atrium, aorta, and left
ventricle
76. The form of circulatory shock known as
hypovolemic shock is:
a. only that form of shock caused by
large-scale loss of blood.
b. any condition in which blood vessels
are inadequately filled and blood cannot circulate normally.
c. shock that results from large-scale
loss of blood volume, or after severe vomiting or diarrhea.
d. always fatal.
78. Peripheral resistance:
a. decreases with increasing length of
the blood vessel.
b. increases as blood vessel diameter
increases.
c. increases as blood viscosity
increases.
d. is not a major factor in blood
pressure in healthy individuals.
80. The arteries that are also called
distributing arteries are the:
a. elastic arteries.
b. muscular arteries.
c. arterioles.
d. capillaries.
82. Which of the following do not influence
arterial pulse rate?
a. activity
b. postural changes
c. emotions
d. sleep
83. Brain blood flow autoregulation:
a. is less sensitive to pH than to a decreased
oxygen level.
b. causes constriction of cerebral blood
vessels in response to a drop in systemic blood pressure.
c. is abolished when abnormally high CO2
levels persist.
d. is controlled by cardiac centers in
the pons.
84. Aldosterone will:
a. promote an increase in blood pressure.
b. promote a decrease in blood volume.
c. result in a larger output of urine.
d. decrease sodium reabsorption.
85. Which of the following is a type of
circulatory shock?
a. hypovolemic, caused by increased blood
volume
b. cardiogenic, which results from any
defect in blood vessels
c. vascular, due to extreme vasodilation
as a result of loss of vasomotor tone
d. circulatory, where blood volume is
normal and constant
87. The term blood islands refers to:
a. embryonic masses of mesodermal cells
that give rise to the endothelial lining of blood vessels.
b. the regions of the liver where
nutrients are extracted from visceral blood.
c. areas of the vascular system where
blood does not circulate.
d. the areas of the pancreas where
insulin is produced.
89. Blood flow to the skin:
a. is controlled mainly by decreasing pH.
b. increases when environmental
temperature rises.
c. increases when body temperature drops
so that the skin does not freeze.
d. is not an important source of
nutrients and oxygen for skin cells.
90. Which statement best describes arteries?
a. All carry oxygenated blood to the
heart.
b. All carry blood away from the heart.
c. All contain valves to prevent the
backflow of blood.
d. Only large arteries are lined with
endothelium.
91. Which tunic of an artery contains
endothelium?
a. tunica interna (intima)
b. tunica media
c. tunica externa
d. tunica adventitia
93. The hepatic portal vein:
a. is actually an artery.
b. carries nutrient-rich blood to the
liver.
c. carries oxygen-rich blood from the
liver to the viscera.
d. carries blood from the liver to the
inferior vena cava.
94. Which of the following is true about veins?
a. Venous valves are formed from the
tunica media.
b. Up to 35% of total body blood is in
venous circulation at any given time.
c. Veins have a small lumen in relation
to the thickness of the vessel wall.
d. Veins are called capacitance vessels
or blood reservoirs.
95. Secondary hypertension can be caused
by:
a. obesity
b. stress
c. arteriosclerosis
d. smoking
98. The pulse pressure is:
a. systolic pressure plus diastolic
pressure.
b. systolic pressure minus diastolic
pressure.
c. systolic pressure divided by diastolic
pressure.
d. diastolic pressure plus 1/3 (systolic
pressure plus diastolic pressure).
100. Histologically, the ________ is
squamous epithelium supported by a sparse connective tissue layer.
a. tunica intima (interna)
b. tunica media
c. tunica externa
d. tunica adventitia
101. Normal blood pressure for an adult at age 65
is:
a. 120/80
b. 90/55
c. 150/90
d. 130/80
102. Which of the following chemicals does not
control blood pressure?
a. ADH
b. atrial natriuretic peptide
c. nitric oxide
d. nitric acid
103. Which of the following blood pressure
readings would be indicative of hypertension?
a. 120/80 in a 30-year-old man
b. 140/90 in a 70-year-old woman
c. 170/96 in a 50-year-old man
d. 110/60 in a 20-year-old woman
104. Mechanisms that do not help
autoregulate blood pressure include:
a. nervous control that operates via
reflex arcs involving pressoreceptors, chemoreceptors, and higher brain
centers.
b. alcohol.
c. renal regulation via the
renin-angiotensin system of vasoconstriction.
d. chemical controls such as atrial
natriuretic peptide.
107. Modified capillaries that are lined
with phagocytes are called:
a. sinuses.
b. sinusoids.
c. thoroughfare channels.
d. anastomoses.
109. Which of the following has an anastomosing
vessel?
a. retina
b. kidney
c. heart
d. spleen
111. Which of the following is not a blood vessel
attached to the circle of Willis?
a. anterior cerebral artery
b. posterior cerebral artery
c. posterior communicating artery
d. anterior communicating artery
112. Select the correct statement about blood
flow.
a. It is relatively constant through all
body organs.
b. It is measured in mm Hg.
c. It is greatest where resistance is
highest.
d. Blood flow through the entire vascular
system is equivalent to cardiac output.
113. In the dynamics of blood flow through
capillaries, hydrostatic pressure:
a. does not play a role.
b. is the same as capillary blood
pressure.
c. generally forces fluid from the
interstitial space into the capillaries.
d. is completely canceled out by osmotic
pressure.
115. The influence of blood vessel diameter on
peripheral resistance is:
a. the only factor that influences
resistance.
b. significant because resistance is
inversely proportional to the fourth power of the vessel radius.
c. significant because resistance is
directly proportional to the blood vessel diameter.
d. insignificant because vessel diameter
does not vary.
116. A patient with essential hypertension might
have pressures of 200/120 mm Hg. This hypertensive state could result in all of
the following changes except:
a. increased work of the left ventricle.
b. increased incidence of coronary artery
disease.
c. increased damage to blood vessel
endothelium.
d. decreased size of the heart muscle.
117. Venous anastomoses:
a. often occlude, causing death if
located in a vital area.
b. connect veins together along their
entire length.
c. form more freely than arterial
anastomoses.
d. occur only in the brain.
119. Fenestrated capillaries:
a. are not more permeable than continuous
capillaries.
b. are not common in endocrine organs and
in areas where capillary absorption is an important function.
c. do not occur in the glomerular
capillaries of the kidneys.
d. are not found in the brain.
120. Cerebral blood flow is regulated by:
a. skin temperature.
b. ADH.
c. intrinsic autoregulatory mechanisms.
d. the hypothalamic
"thermostat."
121. Continuous capillaries:
a. have oval pores to facilitate the
delivery of oxygen and nutrients to tissues.
b. are abundant in the skin and skeletal
muscles.
c. have a thin layer of muscle tissue to
autoregulate blood flow.
d. contain a layer of connective tissue
to prevent protein leakage.
122. Where in the body would you find low oxygen
levels causing vasoconstriction and high levels causing vasodilation?
a. kidney
b. lungs
c. liver
d. heart
123. Permitting the exchange of nutrients
and gases between the blood and tissue cells is the primary function of:
a. arterioles.
b. arteries.
c. veins.
d. capillaries.
125. The circulatory route that runs from the
digestive tract to the liver is called:
a. hepatic portal circulation.
b. pulmonary circulation.
c. coronary circulation.
d. cerebral circulation.
126. Which tunic of an artery is most responsible
for maintaining blood pressure and continuous blood circulation?
a. tunica interna (intima)
b. tunica media
c. tunica externa
d. tunica adventitia
The following statements are true/false:
Answer {a} if true, {b} if false.
131. The left side of the heart pumps the same
volume of blood as the right.
132. An ECG provides direct information about
valve function.
133. Trabeculae carneae are found in the
ventricles and never the atria.
134. Autonomic regulation of heart rate is
via two reflex centers found in the pons.
135. The "lub" sounds of the heart are
valuable in diagnosis because they provide information about the function of
the heart's semilunar valves.
136. The dicrotic notch refers to the brief rise
in pressure caused by the closure of the AV valves during ventricular systole.
137. The mitral valve has chordae but the
tricuspid valve does not.
138. As pressure in the aorta rises due to
atherosclerosis, more ventricular pressure is required to open the aortic
semilunar valve.
139. Proper function of the heart is dependent
upon blood levels of ionic sodium.
140. The myocardium receives its blood supply
from the coronary arteries.
141. Chronic release of excess thyroxine
can cause a sustained increase in heart rate and a weakened heart.
142. Cardiac muscle has more mitochondria
and depends less on a continual supply of oxygen than does skeletal muscle.
143. Congestive heart failure means that
the pumping efficiency of the heart is depressed so that there is inadequate
delivery of blood to body tissues.
144. Tissues damaged by myocardial infarction are
replaced by connective tissue.
145. Proxysmal atrial tachycardia is
characterized by bursts of atrial contractions with little pause between them.
146. In young people, congenital vascular
problems are less common than congenital heart disease.
147. The adjustment of blood flow to each tissue
in proportion to its requirements at any point in time is termed
autoregulation.
148. Vasodilation is a widening of the lumen
due to smooth muscle contraction.
149. Blood flow is
a. inversely proportional to the pressure difference between the two ends of the vessel
b. inversely proportional to the resistance offered by the vessel
c. equal to the viscosity of the blood
150. Normal heart sounds are caused by which of the following events?
a. excitation of the SA node
b. closure of the heart valves
c. friction of blood against the chamber walls
d. contraction of the ventricular myocardium
151. Dilatation of these increases blood flow to a localized tissue bed.
a. arteries.
b. arterioles.
c. capillaries.
d. veins.
e. lymphatics.
152. Damage to the __________ is referred to as heart block.
a. SA node
b. AV valves
c. AV bundle
d. AV node
153. If total peripheral resistance __________, the flow rate through the systemic vessels __________.
a. increases/increases
b. increases/decreases
c. decreases/increases
d. decreases/decreases
e. {b} and {c}
154. When the heart is beating at a rate of 75 times per minute, the duration of one cardiac cycle is __________ second(s).
a. 0.8
b. 1.0
c. 1.2
d. 1.8
155. Vascular compliance = (increase in volume)/(increase in pressure). Now consider two vessels: vessel A, for volume increase VA, pressure increase PA, has a compliance of 1. In vessel B, a pressure increase = 2 × PA results in a the same volume increase, VA. Is vessel B
a. more compliant than A
b. less compliant than A
c. the same compliance as A
156. Select the correct statement about myocardial cell function.
a. The all-or-none law as applied to cardiac muscle means that the entire heart contracts as a unit (functional syncytium) or does not contract at all.
b. Cardiac muscle fibers are each innervated by a sympathetic nerve ending so that the nervous system can increase the heart rate.
c. The refractory period in cardiac muscle is much shorter than that in skeletal muscle.
d. The influx of potassium ions from the transverse tubule lumen into the sarcoplasm is the initiating event in cardiac muscle contraction.
157. The AV valves and semilunar valves are both open during
a. ventricular filling
b. ventricular ejection
c. isovolumic ventricular contraction
d. isovolumic ventricular relaxation
e. none of the above
158. If you were able to alter the membrane permeability of pacemaker cells so that sodium influx would be more rapid,
a. heart rate would decrease
b. calcium channels in the pacemaker cells would be cycling at a greater rate
c. blood pressure would rise due to increased plasma sodium
d. tetanic contraction would occur due to the short absolute refractory period of cardiac muscle
159. In most beds, increased CO2 levels within the tissue bed would result in
a. no vascular changes
b. vasoconstriction
c. vasodilatation
160. Valves are not found in
a. lymphatic vessels
b. arteries
c. veins
d. arteries or veins
161. The period of the cardiac cycle during which the ventricles are contracting is called ventricular
a. diastole
b. ejection
c. systole
162. Isovolumic (isovolumetric) contraction
a. refers to the short period during ventricular systole when the ventricles are completely closed chambers
b. occurs when the AV valves open
c. occurs immediately after the semilunar valves close
d. is indicative of valvular heart disease
163. Which event marks the beginning of ventricular filling?
a. P wave
b. T wave
c. closure of the semilunar valve
d. opening of the AV valves
e. opening of the semilunar valve
164. Most arterioles do not have parasympathetic innervation. Vessels in which of these structures dilate in response to parasympathetic stimulation?
a. liver
b. brain
c. heart
d. clitoris
165. Which statement best describes arteries?
a. All carry oxygenated blood.
b. All carry blood away from the heart.
c. All contain valves to prevent blood from retrograde flow.
d. Only the largest have endothelial linings.
166. The second heart sound is associated with closure of the __________ and occurs during __________
a. AV valves/atrial systole
b. AV valves/ventricular systole
c. semilunar valves/atrial systole
d. semilunar valves/ventricular repolarization
167. The volume of blood ejected from each ventricle with each beat is known as the
a. stroke volume
b. heart rate
c. ventricular ejection fraction
d. cardiac output
168. The influence of blood vessel diameter on peripheral resistance is
a. the only factor that affects resistance
b. very large because resistance is inversely proportional to the fourth power of the vessel radius
c. negligible unless vessel diameter is very large (>2.0 cm)
d. very small because vessel diameter is invariant
169. A 30-year old female with a blood pressure of 120/80, a heart rate of 70, and a stroke volume of 70 mL would have a cardiac output of
a. 6000 mL
b. 4200 mL
c. 4900 mL
d. 70 mL
170. An increase in the heart rate, while the cardiac output remains constant, would
a. increase the stroke volume output.
b. decrease the stroke volume output.
c. have no effect on stroke volume output.
171. In the dynamics of blood flow through the capillaries, capillary hydrostatic pressure
a. does not play a role
b. is the blood pressure
c. generally forces fluid from the interstitial space into the capillary
d. is completely canceled out by the blood osmotic pressure
172. If a person has a blood pressure of 120/80, then the pulse pressure would be
a. 40 mmHg.
b. 45 mmHg.
c. 125 mmHg.
d. 80 mmHg.
173. Modified capillaries that are lined with phagocytes are called
a. sinuses
b. sinusoids
c. thoroughfare channels
d. anastomoses
174. Elephantiasis is caused by
a. reactive hyperemia
b. the filarial parasitic worm
c. protein deficiency
175. Which of these factors would increase the end-diastolic volume?
a. increased force of ventricular contraction
b. increased pulmonary resistance
c. decreased peripheral [systemic] resistance
d. AV-nodal block
176. Select the correct statement about blood flow.
a. Blood flow is constant in all body organs.
b. Blood flow is measured in the units mm Hg.
c. Blood flow is greatest where the resistance is the highest.
d. Blood flow through the entire vascular system is equivalent to the cardiac output.
177. Which vessels are the major sites of resistance in the vascular system?
a. arteries
b. arterioles
c. capillaries
d. veins
178. Which of the following factors would increase arterial pressure (assuming all other factors remained unchanged)?
a. decreased stroke volume
b. vasodilatation
c. decreased heart rate
d. increased total peripheral resistance
e. anemia
179. The driving force for blood flow through a capillary bed is
a. an increased plasma oncotic pressure
b. gravity
c. precapillary arteriolar constriction
d. a pressure difference between the proximal and distal ends of the capillary
180. Aldosterone will
a. promote an increase in blood pressure
b. promote a decrease in blood volume
c. result in a larger urinary output
d. decrease sodium reabsorption
181. Let us assume that we have two blood vessels, A and B. The diameter of vessel A is 10 µm, that of B 30 µm. If the pressure drop across the two vessels is the same, what is the flow in B if the flow in A is 5 µl/sec?
a. 5 µl/sec
b. 15 µl/sec
c. 45 µl/sec
d. 405 µl/sec
182. Peripheral resistance
a. decreases with increasing length of a blood vessel
b. increases as blood vessel diameter increases
c. increases as blood viscosity increases
d. is never a major factor in blood pressure in healthy individuals
183. These are the blood reservoirs; more than half the blood is found in them.
a. arteries
b. arterioles
c. capillaries
d. veins
e. lymphatics
184. Fenestrated capillaries are
a. not more permeable than continuous capillaries
b. least common in endocrine organs and where capillary absorption is important
c. absent from glomerular capillaries in the kidney
d. not found in the brain
The following statements are true/false:
Answer {a} if true, {b} if false.
201. Autoregulation is the adjustment of blood flow to each tissue in proportion to its requirements at any point in time.
202. All the blood in each ventricle is ejected during systole.
203. Osmotic pressure is the force exerted by a fluid pressing against a wall.
204. Vasodilatation is the widening of the vessel lumen due to smooth muscle contraction.
205. When blood flows from very small diameter vessels into larger diameter vessels, the resistance decreases.
206. Reflexes that regulate blood pressure are integrated at the brain stem level.
207. An increase in blood viscosity will cause an increase in peripheral resistance.
208. The cardiac index normalizes an individual’s cardiac output to body surface area to allow for a better comparison of cardiac function. If this were not done, then a morbidly obese individual with a cardiac output of 4.2 l/min would appear healthier than a thin person with a cardiac output of 4.0 l/min.
209. The pancreas is an example of an organ that
does not anastomose.
210. An increase in blood viscosity will cause an
increase in peripheral resistance.
211. Osmotic pressure is created by the
presence in a fluid of small diffusible molecules that easily move through the
capillary membrane.
212. The circle of Willis is an arterial
anastomosis.
213. Arteries supplying the same territory
are often parallel with one another, forming arterial anastomoses.
214. A precapillary sphincter is a cuff of smooth
muscle that regulates the flow of blood into the capillaries.
215. An obstruction in the superior vena cava
would decrease the flow of blood from the head and neck to the heart.
216. The first major branch of the femoral artery
is the pedis artery.
217. The most common form of shock is hypovolemic
shock.
218. Every minute, about 1.5 ml of fluid leaks
out of the capillaries.
219. The azygos vein originates in the abdomen.
220. The pulmonary circulation does not directly
serve the metabolic needs of body tissues.
221. Hypotension is generally considered
systolic blood pressure that is below 100 mm Hg.
222. Thoroughfare channels indirectly
connect an arteriole to a venule.
223. The outermost layer of a blood vessel is the
tunica intima.
224. Arterial pressure in the pulmonary
circulation is much higher than in the systemic circulation because of its
proximity to the heart.
225. The thick-walled arteries close to the heart
are called muscular arteries.
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