AP BIOLOGY

Detailed explanation-1: -Vasoconstriction is a response to being too cold. The process involves the narrowing of blood vessels at the skin surface to reduce heat loss through the surface of the skin. Vasodilation is a response to being too hot.

Detailed explanation-2: -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-3: -Vasoconstriction is the narrowing (constriction) of blood vessels by small muscles in their walls. When blood vessels constrict, blood flow is slowed or blocked. Vasoconstriction may be slight or severe. It may result from disease, drugs, or psychological conditions.

Detailed explanation-4: -Vasodilation occurs when the blood vessels of the skin dilate, and the flow of the blood to the surface is increased. An increased flow of blood to the skin increases the amount of heat loss from the blood vessels of the skin to the environment, increasing 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.