Peripheral resistance reaches its maximum in_______________?
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Answer: C. Arteriole
Explanation
Arterioles possess thick layers of vascular smooth muscle surrounding their endothelial lining. Contraction of this smooth muscle creates the greatest resistance to blood flow in circulation. Poiseuille law dictates that vessel radius strongly dictates hydrodynamic resistance values. The arterial system branches progressively into smaller vessels culminating in arterioles. Arterioles act as primary control valves regulating systemic blood pressure and tissue perfusion. Precappy sphincters further fine-tune local capillary blood flow within target tissues.
Changes in arteriolar resistance directly alter overall systemic blood pressure dynamics. Vasoconstriction in these vessels increases afterload placed upon the contracting left ventricle. Local metabolic factors frequently adjust arteriolar caliber to match tissue oxygen demands. The aorta has a large diameter offering minimal resistance to high-velocity blood flow. Major arteries serve as conduit vessels with relatively low resistance to pressure drops. Veins possess high compliance and large diameters, contributing very little total resistance.
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