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Question
Give scientific reason.
Arteries are thicker than veins.
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Solution
- Arteries carry oxygenated blood away from the heart to the body.
- The blood pumped out by the heart is under high pressure and to withstand this pressure arteries are thick-walled.
- Veins carry deoxygenated blood from the body back to the heart.
- They are thin-walled as the blood that flows through veins is under low pressure. Hence, arteries are thicker than veins.
- Veins, on the other hand, have thinner walls and a bigger lumen since they do not need to resist high pressure like arteries.
- Furthermore, because veins convey relatively low-pressure blood, they are frequently fitted with valves to promote unidirectional blood flow towards the heart.
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