Question

when an individual is exercising, what occurs to the blood vessels in the dermis? vasoconstriction occurs to reduce the amount of heat lost. vasodilation occurs to increase the amount of heat lost. nothing; blood vessels do not change. both vasodilation and vasoconstriction occur when there is excess body heat.

Explanation:

During exercise, the body generates heat. Vasodilation of blood vessels in the dermis occurs to increase blood - flow to the skin surface, allowing for more heat to be dissipated to the environment. Vasoconstriction would reduce heat loss, which is not what happens during exercise. Blood vessels do change during exercise, and it's mainly vasodilation that occurs for heat - loss purposes, not both vasodilation and vasoconstriction simultaneously in this context.

Answer:

Vasodilation occurs to increase the amount of heat lost.