Final answer:
Arteries carry oxygenated blood from the heart to the body and have thick, muscular walls to withstand high pressure. Veins transport deoxygenated blood back to the heart, have thinner walls than arteries, and possess valves to prevent backflow of blood.
Step-by-step explanation:
The core difference between an artery and a vein lies in the type of blood they carry and the direction in which they carry it. Arteries carry oxygenated blood (except for the pulmonary artery) from the heart to other parts of the body. Their walls are thick and muscular to withstand the pressure of the blood that is being pumped by the heart. They're responsible for providing the body's cells with the oxygen they need to function.
On the other hand, veins carry deoxygenated blood (except for the pulmonary veins) back to the heart from other parts of the body. The walls of veins are not as thick as those of arteries because the blood pressure in veins is lower. Veins have valves to prevent the backflow of blood.
Arteries carry oxygenated blood from the heart to the body and have thick muscular walls; Veins carry deoxygenated blood back to the heart from the body and have thinner walls with valves.
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