Differences in structures of artery and veins:
1. Artery has a small lumen, while vein has a larger lumen.
2. Artery is made up of thick, muscular and elastic wall, while vein only has a thin wall. This is because artery has to withstand a high blood pressure while the pressure in veins are low.
3. Arteries are located in very deep under the skin, while veins can be found very near the skin surface. This is because to ensure arteries won't be damaged easily, as they're the main source of oxygen and nutrients for different organs and tissues.
4. Valves can be found in veins but not arteries. As the blood pressure in arteries are high, they don't need an extra driving force to ensure one way flow of blood.
Differences in functions of arteries and veins:
1. Arteries carry blood away from heart to other organs and tissues while veins carry blood from organs to heart.
2. The pressure in arteries are high, while lower pressure in veins.
3. Arteries (except pulmonary artery) carry oxygenated blood and blood filled with nutrients, while veins (except pulmonary vein) carry deoxygenated blood and blood filled with waste.
4. Pulmonary artery carries deoxygenated blood and waste from heart to lungs for gas exchange, while pulmonary vein carries oxygenated blood and nutrients from lungs back to the heart.
Hopefully these 8 differences helped!
