Which of the following statements about arteries is true?

• A. They carry blood away from the heart
• B. They carry blood toward the heart
• C. They exchange gases with tissues
• D. They carry deoxygenated blood only

Answer: (A)

Arteries are defined by the direction of blood flow relative to the heart: they carry blood away from the heart. This is true for systemic arteries, which deliver oxygen-rich blood to tissues and have thick, muscular walls to withstand the heart’s high-pressure ejecta. Gas exchange isn’t a function of arteries; it takes place mainly in capillaries, where oxygen and carbon dioxide are exchanged with tissues. The pulmonary arteries are an exception in that they carry blood away from the heart to the lungs and are deoxygenated, but they still move blood away from the heart. So the statement that arteries carry blood away from the heart is the correct, general description.