Question 1

Which of the following is a sign of ischemia?

Accepted Answer

ST segment depression is a common sign of ischemia on an electrocardiogram (ECG). Absence of R waves, ST segment located on the isoelectric line, and P wave inversion may not be specific signs of ischemia.

Question 2

The rapid change in polarization is known as ________.

Accepted Answer

The rapid change in polarization refers to the rapid depolarization and repolarization of the cell membrane during an action potential. Therefore, choice C, action potential, is the best answer. Repolarization and contraction both refer to specific parts of the cardiac cycle, but do not encompass the entire event.

Question 3

The U wave, which follows the T wave in an ECG tracing, represents:

Accepted Answer

The U wave in an ECG tracing is thought to represent the repolarization of the Purkinje fibers and the bundle of His, although its exact origin is not fully understood. It is a small wave that follows the T wave and is not always present in every ECG.

Question 4

You are working in an outpatient facility that performs ECGs by appointment. You go to the lobby to call your next patient. The patient gets up and comes with you, but you notice that he is out of breath. When you ask, he tells you that he works only two blocks away, but he was held up at the office and had to run in order to make his appointment time. Which of the following is your best course of action?

Accepted Answer

Performing an ECG on a patient whose vital signs are not at their resting state can lead to inaccurate results. It is best to wait until the patient's heart rate and breathing have returned to normal before conducting the test. This ensures the accuracy of the ECG and is in the best interest of the patient's health.

Question 5

Where is the PR interval measured?

Accepted Answer

The PR interval is measured from the beginning of the P wave to the beginning of the QRS complex, representing the time it takes for the electrical impulse to travel from the atria to the ventricles.

Question 6

The QRS complex represents:

Accepted Answer

The QRS complex represents ventricular depolarization. The electrical signal travels through the atria and then through the atrioventricular (AV) node, and then spreads throughout the ventricles, causing them to contract. This depolarization is represented by the QRS complex on an electrocardiogram (ECG).

Question 7

The ST segment represents

Accepted Answer

The ST segment represents the time between ventricular depolarization and the beginning of ventricular repolarization. This period is significant because it is when the ventricles are contracted and there is pressure in the heart's chambers, which can affect blood flow and oxygen supply to the heart muscle. Changes to the ST segment can indicate various heart conditions, including myocardial infarction. The other options are not accurate descriptions of the ST segment.

Question 8

The J point is the

Accepted Answer

The J point is the junction of the QRS interval and the ST interval, marking the end of depolarization and the beginning of repolarization.

Question 9

On an ECG tracing, the period of time from the start of ventricular depolarization to the end of ventricular repolarization is the:

Accepted Answer

The period of time from the start of ventricular depolarization to the end of ventricular repolarization is known as the QT interval, which is measured from the beginning of the QRS complex to the end of the T wave. The U wave is a small positive deflection that can sometimes be seen after the T wave. The ST segment represents the period of time when the ventricles are fully depolarized and is measured from the end of the S wave to the beginning of the T wave. The PR interval represents the time it takes for the electrical impulse to travel from the atria to the ventricles and is measured from the beginning of the P wave to the beginning of the QRS complex.

Question 10

A sudden loss of blood supply and oxygen to a region of heart tissue is known as:

Accepted Answer

The answer of A sudden loss of blood supply and...

Question 11

The QRS complex on an ECG tracing represents:

Accepted Answer

The QRS complex on an ECG tracing represents ventricular depolarization and contraction.

Question 12

The first positive wave in a normal QRS complex is the R wave, which represents conduction of the electrical impulse:

Accepted Answer

The R wave represents conduction of the electrical impulse to the left ventricle, which is the main pumping chamber of the heart. The impulse passes through the ventricles, causing them to contract and pump blood out to the rest of the body.

Question 13

A complete ECG waveform is called a(n):

Accepted Answer

A complete ECG waveform, which includes a P wave, QRS complex, and T wave, is called a complex.

Question 14

Match the numbers from the figure to the correct structure located on the chest. 
- 
A. Diaphragm ________
B. Apex of heart ________
C. Intercostal space ________
D. Sternum ________
E. Base of heart ________
F. Midclavicular line ________
G. Heart ________

Accepted Answer

The answer of Match the numbers from the figure to...

Question 15

Which of the following is not included in the QT interval?

Accepted Answer

The QT interval is measured from the beginning of the Q wave to the end of the T wave on an electrocardiogram (ECG). The P wave represents atrial depolarization, which occurs before the QT interval, and is not included in the measurement. The R wave represents the upstroke of the QRS complex, which occurs during the QT interval. The T wave represents ventricular repolarization, which is included in the QT interval. The ST segment is the flat section between the end of the S wave and the beginning of the T wave, and is also included in the QT interval.

Question 16

You are preparing to perform an ECG on a young woman when she tells you that she just had her blood tested and her blood potassium level is very low. What might you expect to see on the ECG tracing as a result of this?

Accepted Answer

Low potassium levels can cause the heart rate to slow down and the heart contractions to become longer than normal.

Question 17

An interval on an ECG tracing is:

Accepted Answer

An interval on an ECG tracing refers to the period of time between two activities within the heart, such as the time between atrial depolarization and ventricular depolarization (PR interval) or the time between ventricular depolarization and repolarization (QT interval). Therefore, option A is the correct answer, while options B, C, and D are incorrect.

Question 18

The conduction of the electrical impulse through both ventricles appears on an ECG tracing as the:

Accepted Answer

The conduction of the electrical impulse through both ventricles results in the depolarization of the ventricles and the production of the QRS complex on an ECG tracing. The S wave is the downward deflection that follows the Q wave in the QRS complex. Therefore, choice B, S wave, is the correct answer. The P wave represents the depolarization of the atria. The Q wave is often the first downward deflection seen in the QRS complex and may indicate damage to the conduction system or a previous myocardial infarction. The U wave is a small, usually invisible, deflection that follows the T wave and may represent repolarization of the Purkinje fibers or electrolyte imbalances.

Question 19

Repolarization of the cells causes the heart muscle to:

Accepted Answer

Repolarization of the cells refers to the resetting of the electrical charge of the heart muscle cells, which allows them to return to their resting phase and prepare for another contraction. It does not cause the chambers of the heart to eject, infarct, or contract.

Question 20

Ventricular repolarization is represented on the ECG tracing by the:

Accepted Answer

Ventricular repolarization is represented by the T wave on an ECG tracing. The R wave represents ventricular depolarization, while the Q and S waves are part of the QRS complex and also represent ventricular depolarization.

Quiz 2: The Cardiovascular System

Which of the following is a sign of ischemia?

The rapid change in polarization is known as ________.

The U wave, which follows the T wave in an ECG tracing, represents:

Where is the PR interval measured?

The QRS complex represents:

The ST segment represents

The J point is the

On an ECG tracing, the period of time from the start of ventricular depolarization to the end of ventricular repolarization is the:

A sudden loss of blood supply and oxygen to a region of heart tissue is known as:

The QRS complex on an ECG tracing represents:

The first positive wave in a normal QRS complex is the R wave, which represents conduction of the electrical impulse:

A complete ECG waveform is called a(n) :

Match the numbers from the figure to the correct structure located on the chest. - A. Diaphragm B. Apex of heart C. Intercostal space D. Sternum E. Base of heart F. Midclavicular line G. Heart

Which of the following is not included in the QT interval?

You are preparing to perform an ECG on a young woman when she tells you that she just had her blood tested and her blood potassium level is very low. What might you expect to see on the ECG tracing as a result of this?

An interval on an ECG tracing is:

The conduction of the electrical impulse through both ventricles appears on an ECG tracing as the:

Repolarization of the cells causes the heart muscle to:

Ventricular repolarization is represented on the ECG tracing by the:

Quiz 2: The Cardiovascular System

Which of the following is a sign of ischemia?

The rapid change in polarization is known as ________.

The U wave, which follows the T wave in an ECG tracing, represents:

Where is the PR interval measured?

The QRS complex represents:

The ST segment represents

The J point is the

On an ECG tracing, the period of time from the start of ventricular depolarization to the end of ventricular repolarization is the:

A sudden loss of blood supply and oxygen to a region of heart tissue is known as:

The QRS complex on an ECG tracing represents:

The first positive wave in a normal QRS complex is the R wave, which represents conduction of the electrical impulse:

A complete ECG waveform is called a(n) :

Match the numbers from the figure to the correct structure located on the chest. - A. Diaphragm ________ B. Apex of heart ________ C. Intercostal space ________ D. Sternum ________ E. Base of heart ________ F. Midclavicular line ________ G. Heart ________

Which of the following is not included in the QT interval?

You are preparing to perform an ECG on a young woman when she tells you that she just had her blood tested and her blood potassium level is very low. What might you expect to see on the ECG tracing as a result of this?

An interval on an ECG tracing is:

The conduction of the electrical impulse through both ventricles appears on an ECG tracing as the:

Repolarization of the cells causes the heart muscle to:

Ventricular repolarization is represented on the ECG tracing by the:

Match the numbers from the figure to the correct structure located on the chest. - A. Diaphragm B. Apex of heart C. Intercostal space D. Sternum E. Base of heart F. Midclavicular line G. Heart