← Biology (0610)
Q1 / 5
Blood vessels
Higher
2 marks
Why do veins have valves but arteries do not?
A
Veins carry blood at low pressure towards the heart; valves prevent backflow. Arteries have high pressure so need no valves.
B
Arteries have valves but veins do not, because arteries carry oxygenated blood
C
Both arteries and veins have valves; capillaries do not
D
Veins need valves because they are narrower than arteries
Need a hint?