Question

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Q11. Give reasons why:
1 Arteries have thick walls but veins do not.
2 Veins have valves but arteries do not.
3 Capillaries are having permeable membrane but do not have a specific colour like arteries
and veins.​

Answer 1

Answer:

Answer1

Arteries and arterioles have relatively thick muscular walls because blood pressure in them is high and because they must adjust their diameter to maintain blood pressure and to control blood flow. ... Veins may dilate to accommodate increased blood volume.

Answer2

Arteries carry oxygenated blood away from the heart. ... Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.)

Explanation:

I am sorry I can't help you with the last Question.

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