ANIMAL PHYSIOLOGY
OSMOREGULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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vasodilation-more blood near the surface of the skin
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vasoconstriction-less heat near the surface of the skin
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Detailed explanation-1: -Vasodilation is a response to being too hot. The process includes the widening of blood vessels at the skin surface to increase heat loss through the surface of the skin.
Detailed explanation-2: -In warm temperatures, these same blood vessels dilate or widen, increasing the flow of blood to the skin surface, thus allowing heat to leave the body, and keeping the core body temperature from rising to a dangerous level.
Detailed explanation-3: -Cutaneous vasodilation increases blood flow to the skin severalfold, substantially increasing convective transfer of heat from the core to the periphery.
Detailed explanation-4: -Body heating inhibits the tonic activity of the vasoconstrictor nerves through reflexes initiated by elevated internal and skin temperatures. As body heating increases in duration and internal temperature increases significantly, a sympathetic cholinergic active vasodilator system is activated in nonglabrous skin.
Detailed explanation-5: -SKIN TEMPERATURE AND BLOOD FLOW Peripheral vasodilation, as evidenced by increased skin temperature, occurs during hot flashes in all body areas that have been measured (Fig. 1) [12].