What is the difference between arteries and veins?

The distinction between arteries and veins centers on their respective roles in the circulatory system. Arteries are blood vessels that transport blood away from the heart to various parts of the body. This process is vital for delivering oxygen and nutrients to cells for their metabolic needs. In contrast, veins are responsible for carrying blood back to the heart after it has circulated through the body.

Additionally, the structure of arteries and veins supports their functions. Arteries are typically thicker-walled and more muscular, allowing them to withstand and regulate the high pressure of blood pumped directly from the heart. Veins, conversely, have thinner walls and often contain valves to aid the return of blood against gravity, especially from the extremities. While the option indicating oxygenated versus deoxygenated blood has its merits, it's essential to clarify that not all arteries carry oxygenated blood (the pulmonary artery carries deoxygenated blood to the lungs), and not all veins carry deoxygenated blood (the pulmonary veins carry oxygenated blood from the lungs to the heart).

Thus, stating that arteries carry blood away from the heart, while veins carry it back, is an accurate and clear description of their fundamental functions within the circulatory system.