How do blood vessels help to control body temperature.

Body temperature must be maintained around 37°C as the enzymes in our body work best at this temperature. The thermoregulatory centre in the brain contains receptors that detect the temperature of blood, as well as receives information from temperature receptors in the skin. This thermoregulatory centre then sends impulses to the blood vessels (capillaries) in the skin, causing them to become narrower (vasoconstriction) or wider (vasodilation).Blood in the skin can lose heat to the environment through radiation. When the body temperature is too low, the capillaries constrict so that less blood flows through the skin and, therefore, less heat is lost. When the body temperature is too high, the capillaries dilate so that more blood flows through the skin and, therefore, more heat is lost.