Question

why do the arteries have thick elastic walls and veins have valves

Answer 1

arteries have thick elastic walls because they carry blood from heart to all the body parts with a very high pressure. so the thick walls are present to accommodate pressure.
veins carry blood from all body parts to heart. so in order to avoid backward flow of blood, valves are present.

I hope it will help you

Answer 2

ANSWER....

arteries are blood vessels that carry blood away from the heart to other tissues. these large arteries are under the highest blood pressure and have thick elastic walls.

Because viens are under low pressure they have only one way valve that keep blood moving to what the heart and prevent backflow.



hope it helps
thanks...