Name two structural differences between arteries and veins.
- Arteries have thick, elastic, muscular walls whereas veins have thin walls with few elastic fibres. Arteries need these properties to give them the strength and elasticity needed to cope with the high pressure surges of oxygenated blood coming from the heart. The elasticity allows the walls to recoil back to their original shape after they have increased in diameter to allow the surge of blood through. 2. Veins have one-way valves whereas arteries do not have any valves.Veins need valves as the blood flowing through them is at such a low pressure that they need something to prevent it going backwards! They are needed to prevent blood pooling. Arteries do not need valves as the blood is flowing at such a high pressure that it cannot go backwards.
JW
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