What term describes any of the branching muscular and elastic-walled vessels that carry blood from the heart to the body?

• A. Artery
• B. Vein
• C. Aorta
• D. Capillary

Answer: (A)

Arteries are the vessels that carry blood away from the heart. They have thick, muscular walls and a high content of elastic tissue in their walls, which lets them withstand the strong pressure generated by each heartbeat and recoil to help propel blood forward. As they move away from the heart, arteries branch into smaller arteries and arterioles, delivering blood to tissues throughout the body. The aorta is just the largest example of an artery, but the term described in the question refers to this whole category of branching muscular and elastic-walled vessels. Veins, by contrast, return blood to the heart and have thinner walls with valves, while capillaries are the tiny one-cell-thick vessels where exchanges with tissues occur.