PATHOLOGY MCQ
BLOOD VESSELS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -Veins have valves which allow blood to flow only in one direction. Arteries do not have valves.
Detailed explanation-2: -Many veins, particularly those in the arms and legs, have one-way valves. Each valve consists of two flaps (cusps or leaflets) with edges that meet. Blood flowing toward the heart pushes the flaps open like a pair of one-way swinging doors.
Detailed explanation-3: -Veins have valves which stop the blood from flowing backward. This is because blood pressure in veins is very low (compared to arteries).
Detailed explanation-4: -Like veins, arteries do not have valves or they do not need valves as the pressure from the heart is so strong that the flow of blood only takes place in one direction.