Which vessel type has thick elastic walls to withstand high pressures?

• A. Veins
• B. Capillaries
• C. Arteries
• D. Arterioles

Answer: (C)

Vessels that must withstand the high pressures generated by the heart contractions have thick, elastic walls. Arteries fit this role because their walls contain a thick tunica media rich in smooth muscle and elastic fibers. This structure allows the walls to stretch when the heart pumps (systole) and then recoil (diastole), helping to dampen pressure fluctuations and keep blood flowing smoothly.

Veins operate under low pressure and have thinner walls with valves to prevent backflow. Capillaries are extremely thin to allow efficient exchange between blood and tissues. Arterioles do have muscular walls to regulate flow and resistance, but they don’t possess the same thick, elastic walls as arteries. So the vessel best suited to withstanding high pressures is the artery.