Why does the left ventricle have a thicker muscular wall than the right ventricle?
A It must pump blood at higher pressure to reach the entire body
B It receives more deoxygenated blood from the body
C It contains valves that the right ventricle lacks
D It is in direct contact with the lungs
Explanation
The left ventricle pumps oxygenated blood through the *systemic circuit* — every tissue in the body — which requires high pressure. The right ventricle only needs to push blood a short distance to the lungs (pulmonary circuit), so its wall is thinner. Distractors: the left ventricle pumps *oxygenated* blood, not deoxygenated. Both ventricles have valves (AV and semilunar). The right ventricle, not the left, is closer to the lungs.