ATI RN
100 Questions on the Cardiovascular System PDF Questions
Question 1 of 5
The 'lub' sound of the heart is caused by the:
Correct Answer: A
Rationale: The 'lub' sound (first heart sound, S1) occurs at the start of systole when the atrioventricular (AV) valves (tricuspid and mitral) close, preventing backflow into the atria as the ventricles contract.
Question 2 of 5
A client has a diagnosis of bacterial endocarditis (affecting the endocardium). The nurse knows that the client's infection is located in the:
Correct Answer: D
Rationale: The innermost lining of the heart is called the endocardium. The myocardium is the middle, muscle layer of heart tissue. The membrane that surrounds the heart is the pericardium. The mediastinum is the area of the thoracic cavity between the two lungs. (Source: Document, Pretest Answer 1, p. 76)
Question 3 of 5
A client asks the nurse what the higher number in a blood pressure reading means. The nurse responds that the systolic pressure measures the pressure in the:
Correct Answer: D
Rationale: Systolic pressure (the higher number) measures the pressure in the arteries when the ventricles contract (systole), pumping blood into the systemic circulation. Atrial contraction contributes minimally to arterial pressure, and ventricular filling occurs during diastole.
Question 4 of 5
Erythrocyte production:
Correct Answer: B
Rationale: Erythropoiesis requires intrinsic factor from gastric juice for B₁₂ absorption; its loss (e.g., pernicious anemia) reduces RBC production. Estrogen doesn’t directly stimulate it, the spleen isn’t a primary site in adults (bone marrow is), and amino acids aren’t a key trigger.
Question 5 of 5
The structure of hemoglobin A is:
Correct Answer: D
Rationale: Hemoglobin A (adult) has 2 α and 2 β polypeptide chains (globin) and 4 heme groups (iron-containing), allowing it to bind 4 oxygen molecules. ‘Globin molecules’ alone is vague and incorrect.