HISTOLOGY
BLOOD VESSELS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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they constrict (narrow)
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blood flow is increased to the skin (extremities)
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they dilate (widen)
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blow flow is diverted away from the skin (extremities)
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Detailed explanation-1: -Normally, the vessels that supply blood to the skin constrict or narrow in response to cold temperatures. This reaction, called “vasoconstriction, ‘’ decreases blood flow to the skin, which helps to minimize heat loss from the warm blood and therefore preserve a normal internal or “core” temperature.
Detailed explanation-2: -When the skin is exposed to a cold temperature, the blood vessels in the dermis constrict. This allows the blood which is warm, to bypass the skin. The skin then becomes the temperature of the cold it is exposed to. Body heat is conserved since the blood vessels are not diverting heat to the skin anymore.
Detailed explanation-3: -Blood flow to the extremities of the hands and feet respond rapidly upon exposure to cold, with a sympathetically-mediated vasoconstriction reducing blood flow to the peripheries in favor of a central pooling of blood in the torso and deep body core.