ANIMAL PHYSIOLOGY
HUMAN CIRCULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Has valves
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Has thick walls
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Has narrow lumen
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Walls are one cell thick
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Detailed explanation-1: -Veins have valves in them to stop the blood flowing in the wrong direction because it is such a low pressure. Veins often pass between muscles which work with the valves by contracting to force the blood through the vein.
Detailed explanation-2: -Detailed Solution. The veins are the blood vessels that have valves in them. The veins carry deoxygenated blood from body to heart. The veins have valves to ensure blood flows in only one direction.
Detailed explanation-3: -Veins have valves to prevent this backflow of blood. Valves ensure that blood flows only in one direction through veins. Therefore, veins have valves, not the arteries.
Detailed explanation-4: -The blood passing through the veins is deoxygenated (except in pulmonary veins) and flows at a low pressure. It flows slow and steady against the direction of gravity. Therefore, veins have valves to prevent the backflow of blood.
Detailed explanation-5: -Veins have valves which stop the blood from flowing backward.