ATI RN
Cardiovascular System Practice Questions Questions
Question 1 of 5
The condition in which the AV node fails and the electrical stimulus does not reach the ventricles is called a(an)
Correct Answer: A
Rationale: Heart block (A) occurs when AV node failure prevents impulse transmission to ventricles (e.g., third-degree block). MI (B) is tissue death, arrhythmia (C) is irregular rhythm, and ectopic pacemaker (D) is an abnormal impulse source.
Question 2 of 5
Compared to tissue fluid, the osmotic pressure of blood is typically ___; thus water moves into the ___
Correct Answer: A
Rationale: Blood’s osmotic pressure (oncotic, ~25 mmHg) is greater than tissue fluid’s due to plasma proteins (A), drawing water back into capillaries at the venous end. B, C, D mismatch osmosis direction.
Question 3 of 5
The vasomotor center that controls the diameter of blood vessels is located in the
Correct Answer: A
Rationale: The vasomotor center in the medulla oblongata (A) regulates vessel diameter via sympathetic signals. Pons (B), cerebrum (C), and cerebellum (D) have other roles.
Question 4 of 5
The end of the descending aorta branches into the:
Correct Answer: B
Rationale: The descending aorta (abdominal) ends by branching into the common iliac arteries (B) supplying the pelvis and legs. Celiac (A), renal (C), and mesenteric (D) branch earlier.
Question 5 of 5
Thickest layer in heart is:
Correct Answer: D
Rationale: The myocardium (D) is the thickest layer, comprising the heart’s muscular wall (~2-15 mm depending on chamber). Epicardium (A) is a thin serous layer, endocardium (B) is endothelium, and pericardium (C) is the outer sac.