Surface electrodes on the body can capture the heart's electrical activity, creating an electrocardiogram (ECG or EKG).
True
False
The Correct Answer is A
Correct answer: True
Surface electrodes placed on the skin at specific anatomical locations detect the electrical impulses generated by the heart during depolarization and repolarization. These electrodes capture changes in voltage as the cardiac conduction system, including the SA node, AV node, bundle branches, and Purkinje fibers, propagates impulses through the atria and ventricles. The collected signals are transmitted to an electrocardiograph, which records the heart’s electrical activity as an electrocardiogram (ECG or EKG). This test provides critical information about heart rate, rhythm, conduction pathways, and possible ischemic or structural cardiac abnormalities.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
Correct answer: Tachycardia
Tachycardia refers to a heart rate that exceeds the normal resting rate, typically defined as over 100 beats per minute in adults. It can originate from the atria, ventricles, or the sinoatrial (SA) node and may result from physiological responses such as exercise, stress, or fever, as well as pathological conditions including heart failure, anemia, or arrhythmias. Anatomically, tachycardia involves the conduction system of the heart including the SA node, atria, AV node, and ventricles, leading to faster depolarization and contraction.
Correct Answer is C
Explanation
A. The volume of blood remaining in the ventricle after ventricular systole: This refers to the end-systolic volume (ESV), which is the amount of blood left in the ventricle after contraction. While ESV is a component used to calculate stroke volume, it does not itself represent the volume of blood ejected with each heartbeat.
B. The pressure exerted by the left ventricle to open the aortic valve: The pressure generated by the left ventricle during systole is termed ventricular systolic pressure. Although this pressure must overcome aortic pressure to allow ejection, it is a measure of force, not volume, and therefore does not define stroke volume.
C. The difference between end-diastolic volume (EDV) and end-systolic volume (ESV): Stroke volume represents the actual volume of blood ejected from the ventricle with each heartbeat. It is calculated as SV = EDV – ESV. EDV is the total ventricular volume at the end of filling, and ESV is the residual volume after contraction. This difference reflects effective cardiac output per beat.
D. The total volume of blood in the ventricle before contraction: The total volume of blood prior to contraction is the end-diastolic volume (EDV). While EDV contributes to determining stroke volume, it alone does not represent the volume of blood expelled during systole.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.