Question 1

As a result of blockage in the pulmonary artery, blood would first back up into the:
A) aorta.
B) left ventricle.
C) pulmonary veins.
D) right ventricle.

Accepted Answer

The blockage in the pulmonary artery would prevent blood from flowing into the lungs for oxygenation, causing blood to first back up into the right ventricle. This can eventually lead to right ventricular failure, as the heart would have to work harder to pump blood through the blockage.

Question 2

What term represents the period during electrical activity of the heart when no new cardiac potential can be propagated?
A) The absolute refractory period
B) Hyperpolarization
C) The resting phase
D) The cardiac threshold

Accepted Answer

The absolute refractory period is the time during which the heart cannot respond to any new stimulus, ensuring that each heartbeat is a separate event and preventing continuous contraction.

Question 3

What represents the sum of all ventricular muscle cell depolarization?
A) PR interval
B) QRS complex
C) QT interval
D) P wave

Accepted Answer

The QRS complex represents the sum of all ventricular muscle cell depolarization. A represents atrial depolarization, PR interval represents the time for the impulse to travel from the SA node through the AV node, and QT interval represents the time for ventricular depolarization and repolarization.

Question 4

A 50-year-old received trauma to the chest that caused severe impairment of the primary pacemaker cells of the heart. Which of the following areas received the greatest damage?
A) Atrioventricular (AV) node
B) Sinoatrial (SA) node
C) Bundle of His
D) Ventricles

Accepted Answer

The SA node is known as the primary pacemaker of the heart and generates the electrical impulses that initiate each heartbeat. Therefore, severe impairment of the SA node would cause the greatest damage to the heart's primary pacemaker cells. The other options listed (AV node, Bundle of His, and Ventricles) are involved in the conduction of the electrical signal from the SA node and throughout the heart, but they are not the primary pacemaker cells themselves.

Question 5

What does the PR interval viewed on a normal electrocardiogram represent?
A) Atrial depolarization
B) Ventricular depolarization
C) The onset of atrial activation to onset of ventricular activity
D) The "electrical systole" of the ventricles

Accepted Answer

The PR interval represents the time from the onset of atrial depolarization (beginning of the P wave) to the onset of ventricular depolarization (beginning of the QRS complex), indicating the time taken for electrical impulse to travel from the atria to the ventricles.

Question 6

Why does depolarization of a cardiac muscle cell occur?
A) There is a decrease in the permeability of the cell membrane to ions.
B) A rapid movement of ions across the cell membrane occurs.
C) A blockade by calcium ions takes place.
D) There is a stimuli instigated during the refractory period.

Accepted Answer

Depolarization occurs due to the rapid influx of sodium ions into the cell, changing the electrical charge across the cell membrane.

Question 7

What is a function of the pericardium?
A) It provides a barrier against extracardial infections.
B) It serves to improve blood flow through the heart.
C) It plays a role in cardiac conduction.
D) It assists in cardiac contraction.

Accepted Answer

The pericardium is a double-walled sac that surrounds the heart, providing a protective barrier against infection and physical damage. It does not directly improve blood flow, play a role in cardiac conduction, or assist in cardiac contraction.

Question 8

A 20-year-old underwent an echocardiogram to assess chest pain. Results revealed a congenital defect in the papillary muscles. Which of the following would the nurse expect to occur?
A) Closure of the semilunar valve
B) Backward expulsion of the atrioventricular valves
C) Closure of the atrioventricular valve
D) Backward expulsion of the semilunar valves

Accepted Answer

The papillary muscles are responsible for controlling the closing of the atrioventricular valves (mitral and tricuspid valves). A congenital defect in the papillary muscles may result in inadequate closure of these valves, leading to backward expulsion of blood from the ventricles into the atria during systole. This is known as mitral or tricuspid regurgitation. The semilunar valves (pulmonary and aortic) are not directly affected by a defect in the papillary muscles.

Question 9

Which structure would not receive an electrical impulse when the patient is experiencing a left bundle branch block?
A) Atrioventricular (AV) node
B) Sinoatrial (SA) node
C) Bundle of His
D) The left ventricle

Accepted Answer

In a left bundle branch block, the electrical impulse is delayed or blocked in the left bundle branch, preventing it from reaching the left ventricle efficiently.

Question 10

What is the pericardium?
A) The outer muscular layer of the heart
B) The innermost layer of the heart chambers
C) A membranous sac that encloses the heart
D) The heart's fibrous skeleton

Accepted Answer

The pericardium is a double-walled sac that encloses and protects the heart, providing a lubricated environment for its movements.

Question 11

What structure conducts action potentials down the atrioventricular septum?
A) Bachmann bundle
B) Bundle of His
C) Sinoatrial node
D) Atrioventricular node

Accepted Answer

The bundle of His conducts the action potentials down the atrioventricular septum, allowing for coordinated contraction of the ventricles. The Bachmann bundle carries impulses across the atria, the sinoatrial node initiates the electrical signal for the heart to beat, and the atrioventricular node delays conduction to allow for atrial contraction prior to ventricular contraction.

Question 12

Where are the coronary ostia (the openings to the coronary arteries) found?
A) The left ventricle
B) The inferior vena cava
C) The coronary sinus
D) The aorta

Accepted Answer

The coronary ostia are located in the aorta, specifically in the aortic sinuses just above the aortic valve.

Question 13

A 28-year-old with seizure disorder has a vagus nerve stimulator implanted to help control seizure activity. Which result will the nurse expect to occur?
A) Increased speed of cardiac cycle
B) Increased cardiac contractility
C) Decreased vasodilation
D) Decreased cardiac conduction

Accepted Answer

The answer of A 28-year-old with seizure disorder has a...

Question 14

A 13-year-old took a weight loss drug that activated the sympathetic nervous system. Which of the following assessment findings would the nurse expect?
A) Decreased myocardial contraction
B) Decreased heart rate
C) Increased cardiac conduction
D) Increased intranodal conduction time

Accepted Answer

Activation of the sympathetic nervous system leads to increased cardiac conduction, which can result in increased heart rate and increased intranodal conduction time. It is unlikely to cause decreased myocardial contraction or heart rate. However, the use of weight loss drugs in children should be closely monitored and only be recommended under the guidance of a healthcare provider.

Question 15

The cardiac electrical impulse normally begins spontaneously in the sinoatrial (SA) node because it:
A) has a superior location in the right atrium.
B) is the only area of the heart capable of spontaneous depolarization.
C) has rich sympathetic innervation via the vagus nerve.
D) depolarizes between -50 and -60 mV, rather than between -60 and-70 mV.

Accepted Answer

The SA node depolarizes at a higher resting membrane potential (-50 to -60 mV) compared to other cardiac cells, allowing it to reach the threshold for depolarization more easily and initiate the cardiac impulse.

Question 16

What vessel(s) carry oxygenated blood?
A) The superior vena cava
B) Pulmonary veins
C) Pulmonary arteries
D) The cardiac veins

Accepted Answer

Pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart.

Question 17

Which structures act as anchors for the atrioventricular valves?
A) Chordae tendineae
B) Great vessels
C) Coronary ostia
D) Trabeculae carneae

Accepted Answer

Chordae tendineae are thread-like structures that anchor the atrioventricular valves (mitral and tricuspid valves) to the papillary muscles of the ventricles, preventing them from prolapsing into the atria during ventricular contraction.

Question 18

The internal lining of the cardiovascular system is formed by what tissue?
A) Tunica adventitia
B) Connective
C) Mesothelium
D) Endothelium

Accepted Answer

The internal lining of the cardiovascular system is formed by the endothelium. The tunica adventitia is the outer layer, connective tissue is present throughout the walls of blood vessels, and the mesothelium lines the body cavities.

Question 19

Which chamber of the heart generates the highest pressure?
A) Right atrium
B) Left atrium
C) Left ventricle
D) Right ventricle

Accepted Answer

The left ventricle generates the highest pressure because it is responsible for pumping oxygen-rich blood to the rest of the body, requiring a greater force of contraction. The right ventricle, in contrast, only needs to pump blood to the lungs, which have a lower pressure resistance. The atria are not responsible for generating pressure, but rather for receiving blood from the body and lungs, respectively.

Question 20

What is the nurse monitoring when observing the QRS complex on the electrocardiogram?
A) Ventricular activity
B) Pulmonary artery closure
C) Mitral valve opening
D) Aortic valve closing

Accepted Answer

The QRS complex represents ventricular depolarization, or the electrical activity of the ventricles.

Quiz 23: Structure and Function of the Cardiovascular and Lymphatic Systems

As a result of blockage in the pulmonary artery, blood would first back up into the:

What term represents the period during electrical activity of the heart when no new cardiac potential can be propagated?

What represents the sum of all ventricular muscle cell depolarization?

A 50-year-old received trauma to the chest that caused severe impairment of the primary pacemaker cells of the heart. Which of the following areas received the greatest damage?

What does the PR interval viewed on a normal electrocardiogram represent?

Why does depolarization of a cardiac muscle cell occur?

What is a function of the pericardium?

A 20-year-old underwent an echocardiogram to assess chest pain. Results revealed a congenital defect in the papillary muscles. Which of the following would the nurse expect to occur?

Which structure would not receive an electrical impulse when the patient is experiencing a left bundle branch block?

What is the pericardium?

What structure conducts action potentials down the atrioventricular septum?

Where are the coronary ostia (the openings to the coronary arteries) found?

A 28-year-old with seizure disorder has a vagus nerve stimulator implanted to help control seizure activity. Which result will the nurse expect to occur?

A 13-year-old took a weight loss drug that activated the sympathetic nervous system. Which of the following assessment findings would the nurse expect?

The cardiac electrical impulse normally begins spontaneously in the sinoatrial (SA) node because it:

What vessel(s) carry oxygenated blood?

Which structures act as anchors for the atrioventricular valves?

The internal lining of the cardiovascular system is formed by what tissue?

Which chamber of the heart generates the highest pressure?

What is the nurse monitoring when observing the QRS complex on the electrocardiogram?