Final answer:
In cold weather, peripheral blood vessels engage in vasoconstriction to minimize heat loss and preserve core body temperature, as opposed to vasodilation, which occurs in warmth for cooling purposes.
Step-by-step explanation:
In cold weather, peripheral blood vessels generally undergo vasoconstriction. This process reduces blood flow to the surface of the skin, which helps to conserve body heat in vital organs. Vasoconstriction contrasts with vasodilation, which allows for increased blood flow to the skin to facilitate heat loss through radiation and evaporation when the body is overheated. This means that they narrow to reduce blood flow to the skin and retain heat in the body's core. Vasoconstriction helps to maintain body temperature in cold conditions.