Which of the Following Structures Has the Greatest Effect on Systemic

Question

Which of the following structures has the greatest effect on systemic vascular resistance?
A) Veins
B) Arterioles
C) Heart
D) Capillaries

Accepted Answer

Arterioles have the greatest effect on systemic vascular resistance as they are resistance vessels and can contract or relax to control blood flow and pressure in the body's tissues. Veins have a lower resistance as they are capacitance vessels, and capillaries do not have significant smooth muscle control over blood flow. The heart also does not directly affect systemic vascular resistance, although it can impact cardiac output and blood pressure.