Which of the following are examples of blood vessels?

• A. Nerves
• B. Arteries, arterioles, capillaries, venules, veins
• C. Bones
• D. Muscles

Answer: (B)

Blood vessels are the tubes that carry blood throughout the body. The structures that fit this description include arteries, arterioles, capillaries, venules, and veins. Arteries and arterioles move blood away from the heart; capillaries are the thin-walled sites where exchange of oxygen, nutrients, and wastes occurs with tissues; venules and veins return blood toward the heart. Nerves, bones, and muscles are not blood vessels—nerves transmit signals, bones provide support, and muscles serve to move the body and assist with circulation but are not vessels. In phlebotomy, you typically access veins for blood draws.