Heart 3 Flashcards

1
Q

Which of the following is greater?
A. the conduction velocity along a normal
myocardial fiber
B. the conduction velocity along a Purkinje fiber
C. Neither is greater.

A

B. the conduction velocity along a Purkinje

fiber

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2
Q
The pericardial fluid is important because
it
A.	acts as a lubricant.
B.	reduces friction.
C.	acts as a cushion.
D.	none of the above
E.	all of the above
A

E. all of the above

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3
Q
If the connections between the vagus
nerve and the heart are severed, the
A.	heart will beat slower.
B.	stroke volume will decrease.
C.	cardiac output will decrease.
D.	nodal fibers will depolarize more slowly.
E.	none of the above
A

E. none of the above

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4
Q
The function of an atrium is to
A.	collect blood.
B.	pump blood to the lungs.
C.	pump blood into the systemic circuit.
D.	pump blood to the heart muscle.
E.	both A and D
A

A. collect blood.

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5
Q
Depolarization of the ventricles is
represented on an electrocardiogram by
the
A.	P wave.
B.	T wave.
C.	S wave.
D.	QRS complex.
E.	PR complex.
A

D. QRS complex.

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6
Q

Which of the following would be greater?
A. the amount of intracellular calcium ions in
cardiac muscle after beta receptors are
stimulated
B. the amount of intracellular calcium ions in
cardiac muscle after muscarinic receptors are
stimulated

A

A. the amount of intracellular calcium ions in
cardiac muscle after beta receptors are
stimulated

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7
Q

Cardiac output would be greatest when
A. sympathetic stimulation of the heart increases.
B. parasympathetic stimulation of the heart
increases.

A

A. sympathetic stimulation of the heart

increases.

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8
Q
The term used to describe fluid collecting
in the pericardial cavity that restricts the
beating of the heart is known as
A.	cardiac tamponade.
B.	mitral valve prolapse.
C.	pleural effusion.
D.	cardiomyopathy.
E.	pericarditis.
A

A. cardiac tamponade.

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9
Q

Compared to the right ventricle, the left ventricle
has all the following characteristics, except that
it
A. has a thicker wall.
B. is round in cross section.
C. relaxes more slowly.
D. develops higher pressures when it contracts.
E. produces 6 to 7 times more force when it contracts.

A

C. relaxes more slowly.

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10
Q

Which of the following would be greater?
A. the end-diastolic volume when the heart rate
is 150 beats/minute
B. the end-diastolic volume when the heart rate
is 90 beats/minute

A

A. the end-diastolic volume when the heart

rate is 150 beats/minute

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11
Q
The T wave on an ECG tracing represents
A.	atrial depolarization.
B.	atrial repolarization.
C.	ventricular depolarization.
D.	ventricular repolarization.
E.	ventricular contraction.
A

D. ventricular repolarization.

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12
Q

Which of the following would be greater?
A. stroke volume when extracellular calcium ion
concentrations are high
B. stroke volume when extracellular calcium ion
concentrations are low

A

A. stroke volume when extracellular calcium

ion concentrations are high

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13
Q
The following is a list of vessels and structures
that are associated with the heart.
1.	right atrium
2.	left atrium
3.	right ventricle
4.	left ventricle
5.	vena cavae
6.	aorta
7.	pulmonary trunk
8.	pulmonary veins
What is the correct order for the flow of blood
entering from the systemic circulation?
A.	1, 2, 7, 8, 3, 4, 6, 5
B.	1, 7, 3, 8, 2, 4, 6, 5
C.	5, 1, 3, 7, 8, 2, 4, 6
D.	5, 3, 1, 7, 8, 4, 2, 6
E.	5, 1, 3, 8, 7, 2, 4, 6
A

C. 5, 1, 3, 7, 8, 2, 4, 6

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14
Q
The connective tissue of the epicardium at
the interventricular and coronary sulci
generally contains
A.	fat.
B.	arteries.
C.	veins.
D.	both B and C
E.	all of the above
A

E. all of the above

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15
Q

Which of the following is greater?
A. heart rate when acetylcholine is released at
the SA node
B. heart rate when norepinephrine is released at
the SA node

A

B. heart rate when norepinephrine is released

at the SA node

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16
Q
Abnormally slow conduction through the
ventricles would change the shape of the
\_\_\_\_\_ in an ECG tracing.
A.	P wave
B.	T wave
C.	QRS complex
D.	P–R interval
E.	R–T interval
A

C. QRS complex

17
Q
The left and right pulmonary arteries carry
blood to the
A.	heart.
B.	lungs.
C.	brain.
D.	intestines.
E.	liver.
A

B. lungs.

18
Q

Analysis of the electrocardiogram can
reveal all of the following, except the
A. position of the heart in the thoracic cavity.
B. condition of the pulmonary trunk.
C. condition of the conducting system.
D. effects of altered ion concentrations.
E. size of the ventricles.

A

B. condition of the pulmonary trunk.

19
Q
Intercalated discs convey the force of
contraction from cell to cell and propagate
A.	action potentials.
B.	the tendency for late decelerations.
C.	abnormal EKG rhythm.
D.	both A and C
E.	both A and B
A

A. action potentials.

20
Q
The ECG of a person suffering from third-
degree heart block would show
A.	an increased P–R interval.
B.	an inverted P wave.
C.	no visible T wave.
D.	a smaller QRS complex.
E.	more P waves than QRS complexes per
minute.
A

A. an increased P–R interval.

21
Q
Because the heart works continuously, it
requires adequate amounts of oxygen and
nutrients.
A.	True
B.	False
A

A. True

22
Q

The long-term success rate of angioplasty
greatly increases with the use of stents.
A. True
B. False

A

A. True

23
Q
If the membrane of the cardiac muscle cells in
the SA node become more permeable to
potassium ions, the
A.	heart rate will increase.
B.	heart rate will decrease.
C.	membrane will depolarize.
D.	stroke volume will increase.
E.	intracellular concentration of calcium ion will
increase.
A

B. heart rate will decrease.

24
Q
If the connection between the SA node
and AV node becomes blocked,
A.	the ventricles will beat faster.
B.	the ventricles will beat more slowly.
C.	the ventricular rate of contraction will not be
affected.
D.	the stroke volume will increase.
E.	none of the above
A

B. the ventricles will beat more slowly.

25
Q

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

A

A. cardiac arrhythmias may occur.

26
Q

What effect would compressing the inferior vena
cava just below the diaphragm have on cardiac
function?
A. Stroke volume would increase.
B. Cardiac output would increase.
C. Sympathetic stimulation of the heart would increase.
D. all of the above
E. both A and B

A

C. Sympathetic stimulation of the heart would

increase.

27
Q

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

A

B. when parasympathetic stimulation of the heart is

increased

28
Q

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

A

A. when venous return is increased

29
Q

Manganese ion blocks 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 plateau phase of contraction would be shorter.
B. The refractory period would be shorter.
C. The heart would beat less forcefully.
D. The heart rate would increase.
E. The contraction phase would be prolonged.

A

C. The heart would beat less forcefully.

30
Q

David suffers from a regurgitating mitral
valve. This condition would cause
A. increased cardiac output from the right
ventricle.
B. increased cardiac output from the left
ventricle.
C. fluid congestion in the lungs.
D. decreased heart rate.
E. decreased force of cardiac contraction.

A

C. fluid congestion in the lungs.

31
Q

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

A

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