Deck 14: Heart

Question 1

What term refers to the heart's ability to initiate its own electrical impulse?

A) Rhythmicity
B) Automaticity
C) Arrhythmia
D) Ectopy

Answer 1

B

Question 2

What is the endocardium?

A) The outer layer of the heart wall
B) The middle layer of the heart wall
C) The inner layer of the heart wall
D) The sac surrounding the heart

Answer 2

C

Question 3

What effect,if any,would persistent tachycardia have on cardiac output and why?

A) It would have little or no effect because cardiac output is related to stroke volume,not heart rate.
B) It would decrease cardiac output because filling time is decreased,which decreases stroke volume.
C) It would increase cardiac output because tachycardia increases contractility,which increases stroke volume.
D) It would have little or no effect on cardiac output because tachycardia does not affect preload,afterload,or contractility.

Answer 3

B

Question 4

The heart's skeleton

A) electrically insulates the ventricles from the atria.
B) is composed of calcified myocardium.
C) protects the heart from blunt force trauma.
D) protects the SA node.

Question 5

Based on your understanding of how the heart works,which of the heart's chambers would you expect to have the thickest (strongest)walls?

A) Right atrium
B) Right ventricle
C) Left atrium
D) Left ventricle

Question 6

Which of the following factors determines cardiac output?

A) Blood pressure and contractility
B) Heart rate and stroke volume
C) Contractility and stroke volume
D) Heart rate and blood pressure

Question 7

A stenotic aortic valve will increase

A) afterload.
B) stroke volume.
C) preload.
D) contractility.

Question 8

Based on your memory of the heart's electrical system,what will happen if a patient's primary pacemaker fails?

A) The patient will go into cardiac arrest.
B) The atria will stop contracting,but the ventricles will continue to contract.
C) Another area of the electrical system will initiate a heartbeat.
D) Ventricular fibrillation will occur.

Question 9

What is the correct progression of blood through the heart and lungs?

A) Right atrium,right ventricle,lungs,left atrium,left ventricle
B) Right atrium,left atrium,lungs,right ventricle,left ventricle
C) Lungs,right atrium,right ventricle,left atrium,left ventricle
D) Left atrium,lungs,left ventricle,right atrium,right ventricle
E) Left atrium,left ventricle,lungs,right ventricle,right atrium

Question 10

In which area of the brain is the cardiac center located?

A) Frontal lobe
B) Pons
C) Diencephalon
D) Medulla

Question 11

The right coronary artery supplies blood to which area of the heart?

A) Right atrium and most of the right ventricle only
B) Right atrium,most of the right ventricle,and parts of the left atrium and ventricle
C) Right and left atrium only
D) Right atrium,most of the left ventricle,and most of the interventricular septum

Question 12

What is the most likely outcome of mitral valve incompetence?

A) Blood will flow backward into the right atrium.
B) Blood will flow backward into the left atrium.
C) Blood will flow backward into the left ventricle.
D) Blood will flow backward into the right ventricle.

Question 13

What effect will a positive inotropic medication have on cardiac function?

A) It will decrease afterload.
B) It will increase preload.
C) It will increase preload and decrease afterload.
D) It will increase contractility.

Question 14

An area of necrosis develops in the myocardium of the left ventricle as a result of a myocardial infarction.What complication is most likely to occur?

A) An arrhythmia originating in the sinoatrial (SA)node
B) Stenosis of the tricuspid valve
C) A backup of blood into the pulmonary circulation
D) A backup of blood into right ventricle

Question 15

Which blood vessel(s)carries oxygenated blood to the left atrium?

A) Superior vena cava
B) Inferior vena cava
C) Pulmonary arteries
D) Pulmonary veins

Question 16

The series of events that occur from the beginning of one heartbeat to the beginning of the next is the

A) systolic cycle.
B) diastolic cycle.
C) cardiac cycle.
D) atrial-ventricular cycle.

Question 17

Stimulation of the vagus nerve will have what effect on the heart?

A) Increase heart rate
B) Decrease heart rate
C) Increase contractility
D) Decrease contractility

Question 18

A patient who normally has a pulse rate of 82 beats per minute is admitted to the cardiac unit with a pulse rate of 46 beats per minute.Which part of the cardiac conduction system is most likely initiating cardiac impulses?

A) SA node
B) AV node
C) Purkinje fibers
D) Left ventricle

Question 19

The coronary arteries receive their blood supply when

A) the ventricles contract.
B) the atria contract.
C) the atria relax.
D) both ventricles relax.

Question 20

A weak left ventricle will have the greatest impact on

A) preload.
B) contractility.
C) afterload.
D) heart rate.

Question 21

What causes a myocardial infarction?

A) Ischemia in the heart tissue
B) Cigarette smoking and obesity
C) A blood clot or fatty deposit in a coronary artery
D) High blood levels of cholesterol

Question 22

Left-sided heart failure will cause pulmonary ____________________.

Question 23

Damage to the electrical pathway between the SA node and AV node would be reflected by which change on an ECG tracing?

A) An abnormally tall P wave
B) A wide QRS complex
C) A long PR interval
D) A flat ST segment

Question 24

The heart is approximately the size of a human ____________________.

Question 25

What causes the cardiac valves to open and close?

A) Chordae tendineae contract and relax to open and close the valves.
B) Papillary muscles contract and relax to open and close the valves.
C) As the walls of the heart's chambers stretch or relax,they send nervous impulses to the valves,stimulating them to open or close.
D) Pressure changes in the cardiac chambers cause the valves to open and close.

Question 26

The cardiac impulse normally slows down at

A) the bundle of His to wait for the atrial "kick."
B) the AV node to give the atria time to empty and the ventricles time to fill.
C) the SA node to prevent a too rapid heart rate.
D) the Purkinje fibers to give the ventricles time to empty and the atria time to fill.

Question 27

The heart is located in a space in the thoracic cavity called the ____________________.

Question 28

The P wave on an ECG represents ____________________.

Question 29

A heart valve that has become narrowed,such as from scar tissue,is said to be ____________________.

Question 30

What is the average ejection fraction for a healthy heart?

A) 70 percent
B) 95 percent
C) 50 percent
D) 90 percent

Question 31

The ejection fraction is a measurement directly related to

A) contractility.
B) cardiac output.
C) stroke volume.
D) systolic pressure.

Question 32

Which system does the cardiac acceleratory center activate in response to emotional stress or increased physical activity?

A) Sympathetic nervous system
B) Central nervous system
C) Parasympathetic nervous system
D) Autonomic nervous system

Question 33

Two almond-shaped areas of the brain called ____________________ stimulate the increase in heart rate that results from emotions such as fear and anger.

Question 34

The section of the ECG that represents ventricular depolarization is the ____________________.

Question 35

Which of the following correctly identifies the phases of the cardiac cycle?

A) Atrial systole,atrial filling,ventricular systole,ventricular diastole,ventricular filling
B) Passive ventricular filling,atrial systole,isovolumetric contraction,ventricular ejection,isovolumetric relaxation
C) Right atrium,tricuspid valve opens,right ventricle,pulmonary artery to lungs,pulmonary veins to left atrium,mitral valve opens,left ventricle,aortic valve opens,left ventricle contracts
D) Right atrium contracts,right ventricle contracts,left atrium contracts,left ventricle contracts

Question 36

If the amount of blood returning to the left ventricle of a healthy heart increases slightly,according to Starling's law of the heart,what will occur?

A) Blood will back up into the left atrium.
B) Afterload will increase.
C) Contractility will increase.
D) Preload will decrease.

Question 37

Which of the following is a characteristic of the endocardium and why is it important?

A) The endocardium is tough and fibrous,which allows the heart to anchor itself to surrounding structures.
B) The endocardium is thick,which allows the heart to contract forcefully.
C) The endocardium secretes a small amount of serous fluid,which allows the pericardial layers to slide smoothly against one another.
D) The endocardium is smooth,which helps prevent blood clot formation.

Question 38

Starling's law of the heart describes the relationships among

A) end-diastolic ventricular volume,muscle fiber stretching,and contractile force.
B) heart rate,muscle fiber stretching,and cardiac output.
C) blood pressure,peripheral vascular resistance,and venous return.
D) ejection fraction,end-diastolic ventricular volume,and stroke volume.

Question 39

Which receptors detect changes in carbon dioxide and oxygen levels in the blood?

A) Proprioceptors
B) Chemoreceptors
C) Baroreceptors
D) Mechanoreceptors

Question 40

A heart valve that allows blood to leak backward or regurgitate is said to be ____________________.

Question 41

Heart valves are formed by either two or three flaps of tissue called ____________________.

Question 42

The action that supplies the ventricles with the last 30% of blood is called ____________________.

Question 43

The area where the strongest heartbeat can be felt or heard is called the ____________________.