Which type of vessel is classified as a resistance vessel?

Arterioles are classified as resistance vessels because of their primary role in regulating blood flow and systemic vascular resistance. These small-diameter arteries control the distribution of blood to specific organs and tissues by constricting or dilating, thereby influencing blood pressure. The smooth muscle in the walls of arterioles is highly responsive to neural and hormonal signals, allowing for precise adjustments to meet the metabolic needs of the body's tissues. This ability to regulate flow and affect overall circulatory resistance is what distinguishes arterioles from other types of blood vessels.

In contrast, veins are primarily responsible for returning blood to the heart, capillaries are involved in the exchange of materials between blood and tissues, and large arteries serve to conduct blood away from the heart under high pressure without significantly altering the flow dynamics.