NEET BIOLOGY

Detailed explanation-1: -Blood vessels leading to the skin capillaries become wider-they dilate-allowing more blood to flow through the skin and more heat to be lost to the environment. This is called vasodilation .

Detailed explanation-2: -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-3: -Vasoconstriction and vasodilation In endotherms, warm blood from the body’s core typically loses heat to the environment as it passes near the skin. Shrinking the diameter of blood vessels that supply the skin, a process known as vasoconstriction, reduces blood flow and helps retain heat.

Detailed explanation-4: -The thermostat in the blood vessels activates cooling mechanisms. Which of the following occurs when body temperature decreases below normal body temperature? A: Blood vessels in the skin constrict to help prevent heat loss.

Detailed explanation-5: -Blood vessels supplying blood to the skin can swell or dilate-vasodilation. This causes more heat to be carried by the blood to the skin, where it can be lost to the air. Blood vessels can shrink down again-vasoconstriction. This reduces heat loss through the skin once the body’s temperature has returned to normal.