Question

The figures given below show diagrammatic cross-sections of three kinds of blood vessels.

(c) Mention two structural differences between A and B.

Answer 1

Artery	Vein
Progressively branched, decreasing in size	Progressively unite, increasing in size
Smallest artery breaks into arterioles	Smallest vein arises from venules
Have thick and more muscular walls	Have thin and less muscular walls
Walls are elastic	Walls are non-elastic
Have narrower lumen	Have wider lumen
Have no valves	Have valves to prevent backward flow of blood