← 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
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Blood vessels — Biology (0610) | Smartzi