WHY ARTERIES HAVE THICK WALLS.
2.WHY VEINS HAVE THUN WALLS AND WHY THEY HAVE VALVES.
pls ans quickly i have exam on saturday
1. Since arteries have to carry blood from heart to distant body parts, blood flows in them with a very high pressure. To sustain this high pressure arteries are thick walled.
2. Veins have thin wall because, they bring back blood from different organs to the heart and the blood that travels inside the vein do not have to withstand high pressure unlike arteries, so they possess thin wall.
Veins have valves within them in order to prevent back flow of blood. Blood in the veins flow slowly and with a low pressure so there are chances of backflow.
2. Veins have thin wall because, they bring back blood from different organs to the heart and the blood that travels inside the vein do not have to withstand high pressure unlike arteries, so they possess thin wall.
Veins have valves within them in order to prevent back flow of blood. Blood in the veins flow slowly and with a low pressure so there are chances of backflow.