Final answer:
The statement is B) false because dermal blood vessels dilate, not constrict, when body temperature rises to allow more blood to flow near the skin's surface, assisting in heat loss and cooling down the body.
Step-by-step explanation:
The statement that dermal blood vessels are likely to constrict when body temperature rises above normal is false. In fact, the opposite occurs. When the body begins to overheat, as during strenuous physical activities, the mechanisms of thermoregulation within the skin activate to prevent overheating. One of these mechanisms is vasodilation, where the dermal blood vessels dilate to allow more blood from the warm body core to flow close to the surface of the skin. This process increases heat loss by radiation into the environment, which helps to cool the body down. On the contrary, in response to low temperatures, the skin's blood vessels constrict (vasoconstriction) in an effort to minimize heat loss and conserve body heat.