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Flashcards in chapter 14 Deck (85):
1

In the 16th century, William Harvey discovered evidence that
A) the cardiovascular system transports blood and air.
B) arteries and veins are linked by capillaries.
C) the cardiovascular system is an open system.
D) the liver manufactures blood.
E) blood is recirculated instead of consumed.

E) blood is recirculated instead of consumed.

2

2) Capillaries are best described as
A) thin walled vessels that carry blood deficient in oxygen.
B) microscopic vessels in which blood exchanges material with the interstitial fluid.
C) thin walled vessels that convey blood toward the heart.
D) thick walled vessels that carry blood rich in oxygen.
E) thick walled vessels that convey blood away from the heart.

B) microscopic vessels in which blood exchanges material with the interstitial fluid.

3

3) The most accurate definition of artery is a vessel that
A) carries highly oxygenated blood.
B) contains smooth muscle in its wall.
C) transports blood away from the heart.
D) contains internal valves.
E) transports blood toward the heart.

C) transports blood away from the heart.

4

4) The purpose of having valves in the cardiovascular system is to
A) ensure that blood flows in one direction.
B) prevent blood from flowing too quickly.
C) regulate blood pressure.
D) provide the force for circulation.
E) provide sounds so that heart health can be monitored.

A) ensure that blood flows in one direction.

5

5) Which organ is NOT known to include a special portal system for blood?
A) brain
B) kidney
C) liver
D) heart
E) All of these organs have portal systems.

D) heart

6

6) Which artery/arteries branch(es) is/are most proximal to the beginning of the aorta at the heart?
A) pulmonary
B) renal
C) carotid
D) coronary
E) hepatic

D) coronary

7

7) The hepatic portal vein carries blood away from the
A) liver.
B) pancreas.
C) digestive tract.
D) spleen.
E) kidneys.

C) digestive tract.

8

8) The driving force for blood flow is a(n) ________ gradient.
A) gravity
B) osmotic
C) volume
D) pressure

D) pressure

9

9) Which of the following statements about hydrostatic pressure is NOT true?
A) Force is not equal in all directions.
B) The lateral pressure component of moving fluid represents the hydrostatic pressure.
C) If a fluid is not moving, the pressure that it exerts is called hydrostatic pressure.
D) Hydrostatic pressure does not include the dynamic component of a moving fluid.
E) All of the statements are true.

A) Force is not equal in all directions.

10

10) Each of the following changes will result in increased blood flow to a tissue EXCEPT one. Identify
the exception.
A) decreased peripheral resistance
B) increased blood volume
C) relaxation of precapillary sphincters
D) decreased vessel diameter
E) increased blood pressure

D) decreased vessel diameter

11

11) Which parameters are associated with increased resistance?
A) reduced friction
B) increased blood vessel diameter
C) reduced flow
D) decreased viscosity
E) decreased length

C) reduced flow

12

12) As blood vessel length increases,
A) flow decreases only.
B) resistance increases only.
C) friction decreases only.
D) resistance increases and flow decreases.
E) both resistance and flow increase.

D) resistance increases and flow decreases.

13

13) Which of the following will increase flow in a vessel the most?
A) decrease length by 1 unit
B) decrease viscosity by 1 unit
C) increase radius by 1 unit
D) All have the same effect on flow.

C) increase radius by 1 unit

14

14) When a quantity is expressed as "4 cm/sec," what is being described is the
A) pressure gradient.
B) pressure.
C) volume.
D) velocity of flow.
E) flow rate.

D) velocity of flow.

15

15) The sac around the heart is the
A) peritoneum.
B) epicardium.
C) pleural sac.
D) pericardium.
E) myocardium.

D) pericardium.

16

16) The function of the pericardial fluid is to
A) remove waste products from the heart.
B) store calcium for the heart.
C) provide oxygen to the heart.
D) reduce friction between the heart and the pericardium.
E) provide fuel to the heart.

D) reduce friction between the heart and the pericardium.

17

17) At an intercalated disc,
A) two cardiac muscle cells are connected by gap junctions.
B) the cell membranes of two cardiac muscle fibers are completely separated by a synapse.
C) the myofibrils are loosely attached to the membrane of the disc.
D) t-tubules unite the membranes of the adjoining cells.
E) All of the answers are correct.

A) two cardiac muscle cells are connected by gap junctions.

18

18) In the heart, valves are located
A) between atria and ventricles and between ventricles and arteries.
B) just between the ventricles and the arteries.
C) just between the atria and the ventricles.
D) just between the great veins and the atria.
E) just between the right and left ventricles.

A) between atria and ventricles and between ventricles and arteries.

19

19) Which valves have chordae tendineae?
A) bicuspid (mitral) and tricuspid valves
B) semilunar valves
C) valves in veins
D) coronary valves
E) aortic and pulmonary valves

A) bicuspid (mitral) and tricuspid valves

20

20) The term myogenic indicates that the heart muscle is the source of
A) the electrical signal that triggers heart contraction.
B) a hormone that indirectly regulates blood volume.
C) stem cells that repair damaged heart tissue.
D) the contractile force for pumping.
E) receptors that trigger blood pressure reflexes.

A) the electrical signal that triggers heart contraction.

21

21) The action potential in a cardiac contractile cell causes
A) activation of NCX transporters.
B) opening of L-type calcium channels.
C) activation of sodium-potassium ATPase.
D) opening of HCN channels.
E) opening of ryanodine receptor calcium channels.

B) opening of L-type calcium channels.

22

22) Stretching a myocardial cell
A) only decreases the force of a contraction.
B) only increases the force of contraction.
C) only allows more Ca2+ to enter.
D) decreases the force of a contraction and allows more Ca2+ to enter.
E) allows more Ca2+ to enter and increases the force of a contraction.

E) allows more Ca2+ to enter and increases the force of a contraction.

23

23) The rapid depolarization phase of the action potentials of myocardial contractile cells is due to
which ion(s)?
A) Na+ only
B) C a2+ only
C) K+ only
D) both Ca2+ and K+
E) both Na+ and K+

A) Na+ only

24

24) During the plateau phase of the action potentials of myocardial contractile cells, which ion(s) is/are
crossing the membrane?
A) K+ only
B) C a2+ only
C) Na+ only
D) both Ca2+ and K+
E) both Na+ and K+

D) both Ca2+ and K+

25

25) The flattening of the action potentials of myocardial contractile cells, called the plateau phase, is
due to a combination of ________ K+ permeability and ________ Ca2+ permeability.
A) decreasing, increasing
B) increasing, increasing
C) increasing, decreasing
D) decreasing, decreasing

A) decreasing, increasing

26

26) The action potentials of myocardial autorhythmic cells, are due to a combination of increasing
Na2+ ________ and decreasing K+ ________.
A) efflux, influx
B) influx, efflux
C) influx, influx
D) efflux, efflux

B) influx, efflux

27

27) The end of the plateau phase is due to the ________ of Ca2+ channels and ________ of K+ channels.
A) opening, closing
B) closing, opening
C) closing, closing
D) opening, opening

B) closing, opening

28

28) A typical action potential of a myocardial contractile cell lasts ________ millisecond(s).
A) 1-5
B) at least 200
C) at least 500
D) 50-100
E) less than 1

B) at least 200

29

29) The importance of the plateau phase of the action potential of myocardial cells is in
A) preventing overstretching of the cells.
B) enhancing the efficiency of oxygen use by the cells.
C) regulating Ca2+ availability to the cells.
D) preventing tetanus.
E) preventing fibrillation.

D) preventing tetanus.

30

30) Myocardial cells can generate action potentials spontaneously because they have
A) unstable ion channels.
B) a net influx of Na+.
C) L-type Ca2+ channels.
D) permanently open channels for Na+ and K+.
E) prolonged Ca2+ influx

A) unstable ion channels.

31

31) If channels are permeable to
A) Na+ only.
B) C a2+ only.
C) K+ only.
D) Na+ and K+.
E) C a2+ and K+.

D) Na+ and K+.

32

32) Autorhythmic cells
A) have organized sarcomeres.
B) contribute to the force of contraction.
C) are also called pacemakers because they set the rate of the heartbeat.
D) are the same size as myocardial contractile cells.
E) None of the answers are correct

C) are also called pacemakers because they set the rate of the heartbeat.

33

33) The depolarization of the pacemaker action potential spreads to adjacent cells through
A) chemical synapses.
B) tight junctions.
C) gap junctions.
D) desmosomes.

C) gap junctions.

34

34) The fibrous skeleton of the heart is important because it
A) forces electrical activity to be conducted through the atrioventricular node.
B) helps guide the blood into the proper chambers in sequence.
C) directs the flow of blood into the arteries.
D) transmits electrical activity from the atria to the ventricles

A) forces electrical activity to be conducted through the atrioventricular node.

35

35) The AV node is important because it
A) serves as the pacemaker in a normal heart.
B) delays the transmission of the electrical impulses to the ventricles in order for the atria to
finish contracting.
C) electrically opens the AV valves.
D) directs electrical impulses from the ventricles to the atria.
E) None of these answers are correct.

B) delays the transmission of the electrical impulses to the ventricles in order for the atria to
finish contracting.

36

36) The medical term for heart attack is
A) heart murmur.
B) heart failure.
C) fibrillation.
D) heart block.
E) myocardial infarction.

E) myocardial infarction.

37

37) In the condition known as complete heart block, what happens?
A) The mitral valve leaflets calcify and close, preventing blood from being pumped efficiently by
the left side of the heart.
B) Blood flow through the foramen ovale is blocked.
C) Electrical signals from the SA node never reach the ventricles, so the contraction of the atria is
not coordinated with the contraction of the ventricles.
D) The fibrous skeleton of the heart breaks down, interfering with the passage of blood from the
atria to the ventricles.
E) Coronary arteries are blocked by plaques, preventing blood and oxygen from reaching the
myocardial contractile cells.

C) Electrical signals from the SA node never reach the ventricles, so the contraction of the atria is
not coordinated with the contraction of the ventricles.

38

38) When the heart is in fibrillation,
A) effective pumping of the ventricles ceases because the myocardial cells fail to work as a team,
and the brain cannot get adequate oxygen.
B) the myocardial cells are contracting together as they should; fibrillation indicates a normal
sinus rhythm of 75 beats per minute.
C) the myocardial cells may become damaged from contracting too fast.
D) the myocardial cells deplete their oxygen supply because they are contracting too fast, and the
lactic acid produced damages the myocardial cells. E) there is no contraction of the myocardium.

A) effective pumping of the ventricles ceases because the myocardial cells fail to work as a team,
and the brain cannot get adequate oxygen.

39

39) Electrical shock to the heart is usually used to treat
A) atrial fibrillation.
B) heart murmur.
C) myocardial infarction.
D) heart block.
E) ventricular fibrillation.

E) ventricular fibrillation.

40

40) ECGs
A) measure the mechanical activity of the heart.
B) provide direct information about the heart function.
C) are most useful in diagnosing heart murmurs.
D) have two major components: waves and nodes.
E) show the summed electrical potentials generated by all cells of the heart.

E) show the summed electrical potentials generated by all cells of the heart.

41

41) The P wave of an ECG corresponds to
A) the progressive wave of ventricular depolarization.
B) the depolarization of the atria.
C) atrial repolarization.
D) the repolarization of the ventricles.
E) None of the answers are correct.

B) the depolarization of the atria.

42

42) The QRS complex of an ECG corresponds to
A) the repolarization of the ventricles.
B) the depolarization of the atria.
C) atrial repolarization.
D) the progressive wave of ventricular depolarization.
E) None of the answers are correct.

D) the progressive wave of ventricular depolarization.

43

43) A heart rate of 125 beats per minute could be correctly termed
A) bradycardia.
B) an arrhythmia.
C) fibrillation.
D) tachycardia.
E) a normal resting heart rate.

D) tachycardia.

44

44) Ventricular contraction
A) begins just after the T wave.
B) begins just after the Q wave.
C) begins during the latter part of the P wave.
D) begins during the first part of the P wave.
E) None of the answers are correct.

B) begins just after the Q wave.

45

45) Atrial contraction
A) begins during the first part of the P wave.
B) begins just after the Q wave.
C) begins during the latter part of the P wave.
D) begins just after the T wave.
E) None of the answers are correct.

C) begins during the latter part of the P wave.

46

46) In electrocardiography, a lead is a(n)
A) electrode.
B) cable that attaches between the ECG machine and the body.
C) pair of electrodes.

C) pair of electrodes.

47

47) Which event happens at the start of a cardiac cycle?
A) The SA node fires.
B) The P wave develops.
C) Blood is ejected from the atrium.
D) Atrial systole occurs.
E) Ventricular systole occurs

A) The SA node fires.

48

48) In order for blood to enter the heart,
A) the AV valves must be open.
B) the atria must not only be at rest but the atrial pressure must be lower than the veins.
C) the pressure in the atria must be lower than in the veins.
D) the atria must be in diastole.
E) All of the answers are correct.

B) the atria must not only be at rest but the atrial pressure must be lower than the veins.

49

49) Which of the following events result in the first heart sound?
A) The semilunar valves open.
B) The semilunar valves close.
C) The atria contract.
D) The AV valves close.
E) The AV valves open.

D) The AV valves close.

50

50) During the isovolumic phase of ventricular systole,
A) blood is ejected into the great vessels.
B) the ventricles are filling with blood.
C) the atria contract.
D) the atrioventricular valves and semilunar valves are closed.
E) the ventricles are relaxing.

D) the atrioventricular valves and semilunar valves are closed.

51

51) During the cardiac cycle,
A) the P wave of the ECG occurs between the first and second heart sounds.
B) the greatest increase in ventricular pressure occurs during the ejection phase.
C) the second heart sound coincides with the QRS complex of the ECG.
D) the third heart sound occurs during atrial systole.
E) the QRS complex of the ECG precedes the increase in ventricular pressure.

E) the QRS complex of the ECG precedes the increase in ventricular pressure.

52

52) During ventricular systole,
A) the AV valves are closed.
B) the ventricles are relaxed.
C) blood is entering the ventricles.
D) the pressure in the ventricles declines.
E) the atria are contracting.

A) the AV valves are closed.

53

53) During ventricular ejection,
A) the AV valves are open.
B) the semilunar valves are closed.
C) the ventricles are in systole.
D) the QRS complex is just starting.
E) blood is forced into veins.

C) the ventricles are in systole.

54

54) The term used to describe the amount of blood in the ventricle available to be pumped out of the
heart during the next contraction is
A) stroke volume (SV).
B) heart rate (HR).
C) end-systolic volume (ESV).
D) cardiac output (CO).
E) end-diastolic volume (EDV)

E) end-diastolic volume (EDV)

55

55) The volume of blood ejected from each ventricle during a contraction is called the
A) cardiac output.
B) cardiac reserve.
C) end-systolic volume.
D) stroke volume.
E) end-diastolic volume.

D) stroke volume.

56

56) The cardiac output is equal to
A) the difference between the end-diastolic volume and the end-systolic volume.
B) the product of heart rate and stroke volume.
C) the stroke volume less the end-systolic volume.
D) the product of heart rate and blood pressure.
E) the difference between the stroke volume at rest and the stroke volume during exercise.

B) the product of heart rate and stroke volume.

57

57) The term that describes the volume of blood circulated by the heart in one minute is
A) heart rate (HR).
B) end-diastolic volume (EDV).
C) stroke volume (SV).
D) end-systolic volume (ESV).
E) cardiac output (CO).

E) cardiac output (CO).

58

58) Epinephrine and norepinephrine increase ion flow through ________ channels.
A) C a2+ only
B) Na+ only
C) K+ only
D) If only
E) If and Ca2+

E) If and Ca2+

59

59) According to Starling's law of the heart, the cardiac output is directly related to the
A) end-systolic volume.
B) size of the ventricle.
C) venous return.
D) heart rate.
E) thickness of the myocardium.

C) venous return.

60

60) Which of these will increase the heart rate?
A) only the application of epinephrine to the SA node
B) only the application of acetylcholine to the SA node
C) only sympathetic stimulation to the SA node
D) both sympathetic stimulation and application of epinephrine to the SA node
E) both sympathetic stimulation and application of acetylcholine to the SA node

D) both sympathetic stimulation and application of epinephrine to the SA node

61

61) Stimulation of the beta receptors on heart muscle results in
A) decreased force of cardiac contraction.
B) decreased rate of contraction.
C) the formation of cAMP.
D) increased sensitivity to acetylcholine.
E) All of the answers are correct.

C) the formation of cAMP.

62

62) Drugs known as beta blockers will
A) increase stroke volume.
B) decrease the end-systolic volume.
C) decrease heart rate.
D) increase cardiac output.
E) increase heart rate.

C) decrease heart rate.

63

115) Place these structures in the order that blood returning to the heart from the body would pass
through them.
1. right ventricle
2. left atrium
3. right atrium
4. pulmonary artery
5. left ventricle
6. pulmonary vein
A) 1, 3, 6, 4, 5, 2
B) 3, 2, 4, 6, 1, 5
C) 2, 5, 6, 4, 3, 1
D) 4, 2, 5, 6, 3, 1
E) 3, 1, 4, 6, 2, 5

E) 3, 1, 4, 6, 2, 5

64

116) If blood pressure doubled at the same time that the peripheral resistance doubled, the blood flow
through a vessel would be
A) doubled.
B) halved.
C) 1/16 as much.
D) 16 times greater.
E) unchanged.

E) unchanged.

65

117) Which of the following conditions would have the greatest effect on peripheral resistance?
A) doubling the length of a vessel
B) doubling the diameter of a vessel
C) doubling the viscosity of the blood
D) doubling the number of white cells in the blood
E) doubling the turbulence of the blood

B) doubling the diameter of a vessel

66

118) Which statement is NOT true regarding cardiac muscle?
A) The oxygen demand of cardiac muscle cells is high because they have many mitochondria.
B) Cardiac muscle cells rely on a sarcoplasmic reticulum for storage of Ca2+ ions.
C) Cardiac muscle cells must obey the all-or-none law of contraction.
D) Intercalated disks contain both desmosomes for firm attachment and gap junctions to allow
communication.
E) Calcium-induced calcium release is the process by which extracellular Ca2+ triggers the release of stored Ca2+ from the sarcoplasmic reticulum.

C) Cardiac muscle cells must obey the all-or-none law of contraction.

67

119) If the membranes of the cardiac muscle cells in the SA node become more permeable to potassium
ions,
A) the stroke volume will increase.
B) the heart rate will decrease.
C) the intracellular concentration of calcium ion will increase.
D) the heart rate will increase.
E) the membrane will depolarize.

B) the heart rate will decrease.

68

120) As a result of the long refractory period, cardiac muscle cannot exhibit
A) treppe.
B) tonus.
C) fatigue.
D) tetany.
E) recruitment.

D) tetany.

69

121) Ivabrandine selectively blocks If channels in the heart. Which statement would be true concerning a patient who is taking this drug?
A) The amount of calcium entering the patient's heart cells would increase.
B) The drug would slow down this individual's heart rate.
C) This patient must have been suffering from bradycardia.
D) This drug would decrease contractility of the patient's heart.
E) This drug would raise the blood pressure of the patient.

B) The drug would slow down this individual's heart rate.

70

122) Put these autorhythmic cells into the correct order for conveying electrical signals through a
normal heart.
1. bundle of His
2. internodal pathway
3. Purkinje fibers
4. atrioventricular node
5. sinoatrial nodes
6. left and right bundle branches
A) 3, 6, 1, 4, 2, 5
B) 5, 4, 1, 6, 2, 3
C) 5, 2, 4, 1, 6, 3
D) 4, 2, 5, 1, 6, 3
E) 5, 2, 1, 6, 4, 3

C) 5, 2, 4, 1, 6, 3

71

123) The ECG of a person suffering from complete heart block would show
A) a smaller QRS complex.
B) more P waves than QRS complexes per minute.
C) no visible T wave.
D) an inverted P wave.
E) an increased PR interval.

B) more P waves than QRS complexes per minute.

72

125) If a myocardial infarction results in the formation of scar tissue along the pathway of the left bundle
branch,
A) blood flow to the lungs will decrease.
B) conduction through the left ventricle would remain normal.
C) the ventricle will contract more forcefully.
D) cardiac arrhythmias may occur.
E) the right ventricle will fail to contract.

D) cardiac arrhythmias may occur.

73

126) Abnormally slow conduction through the ventricles would change the ________ in an ECG tracing.
A) P wave
B) RT interval
C) QRS complex
D) PR interval
E) T wave

C) QRS complex

74

127) If there is a blockage between the AV node and the AV bundle, how will this affect the appearance
of the electrocardiogram?
A) The PR interval will be smaller.
B) There will be more QRS complexes than P waves.
C) There will be more P waves than QRS complexes.
D) The T wave will disappear.
E) The QRS interval will be longer.

C) There will be more P waves than QRS complexes.

75

128) Put these phases of the cardiac cycle in the correct order.
1. opening of the semilunar valves
2. isovolumic contraction
3. beginning of atrial systole
4. closure of the AV valves
5. completion of ventricular filling
6. beginning of ventricular systole
7. ventricular relaxation
8. ventricular ejection
A) 3, 5, 6, 1, 8, 4, 2, 7
B) 3, 5, 6, 4, 2, 1, 8, 7
C) 3, 2, 6, 4, 5, 8, 7, 1
D) 3, 2, 6, 1, 4, 5, 8, 7
E) 4, 5, 1, 2, 7, 8, 3, 6

B) 3, 5, 6, 4, 2, 1, 8, 7

76

129) Left ventricular pressure is higher than pressure in the aorta during
A) ventricular diastole only.
B) ventricular systole only.
C) atrial systole only.
D) atrial systole and ventricular systole.
E) All of the answers are correct.

A) ventricular diastole only.

77

130) In which of the following situations would the end-systolic volume (ESV) be the greatest?
A) when parasympathetic stimulation of the heart is increased
B) when the force of myocardial contraction is increased
C) when the intracellular stores of calcium are increased
D) when stroke volume is increased
E) when sympathetic stimulation of the heart is increased

A) when parasympathetic stimulation of the heart is increased

78

131) If the EDV is 140 mL, which other values are most likely to occur in a healthy, normal person?
A) The ESV could be 50 mL and the SV could be 90 mL.
B) Diastolic pressure would be equal to EDV.
C) The ESV could be 70 mL and the SV could be 90 mL.
D) The ESV could be 90 mL and the SV could be 50 mL.
E) The cardiac output could be 90 mL.

A) The ESV could be 50 mL and the SV could be 90 mL.

79

132) A certain drug decreases heart rate by producing hyperpolarization in the pacemaker cells of the
heart. This drug probably binds to
A) muscarinic receptors.
B) nicotinic receptors.
C) alpha adrenergic receptors.
D) beta receptors.

A) muscarinic receptors.

80

133) Under which set of circumstances would the diameter of peripheral blood vessels be the greatest?
A) increased sympathetic stimulation
B) increased parasympathetic stimulation
C) decreased sympathetic stimulation
D) decreased parasympathetic stimulation
E) both increased parasympathetic and increased sympathetic stimulation

C) decreased sympathetic stimulation

81

134) Acetylcholine slows the heart rate by
A) just increasing ion influx, thus increasing the rate of depolarization.
B) increasing the permeability to K+ and decreasing the permeability to Ca2+.
C) just increasing the permeability to Ca2+.
D) just decreasing the permeability to Ca2+.
E) just increasing the permeability to K+.

B) increasing the permeability to K+ and decreasing the permeability to Ca2+.

82

135) Sympathetic stimulation increases the heart rate by
A) just increasing the permeability to Ca2+.
B) increasing the permeability to K+ and decreasing the permeability to Ca2+.
C) just decreasing the permeability to Ca2+.
D) just increasing ion influx, thus increasing the rate of depolarization.
E) just increasing the permeability to K+.

D) just increasing ion influx, thus increasing the rate of depolarization.

83

136) In which situation would the stroke volume be the greatest?
A) when the difference between the end-diastolic volume and the end-systolic volume is small
B) when venous return is increased
C) when venous return is decreased
D) when the force of contraction is decreased
E) when calcium channel blockers are present

B) when venous return is increased

84

137) Manganese ions block the calcium channels in the cardiac muscle membrane. How would the
presence of manganese in the extracellular fluid affect the contraction of the heart muscle?
A) The contraction phase would be prolonged.
B) The refractory period would be shorter.
C) The plateau phase of contraction would be longer.
D) The heart would beat less forcefully.
E) The heart rate would increase.

D) The heart would beat less forcefully.

85

138) Drugs known as calcium channel blockers can be used to
A) decrease the force of cardiac contraction.
B) constrict the coronary arteries.
C) increase sympathetic stimulation of the myocardium.
D) increase stroke volume.
E) increase blood pressure.

A) decrease the force of cardiac contraction.