Q. How is the skin involved in the regulation of body temperature?
Skin is one of various organ systems participating in maintaining a core temperature, meaning the temperature near center of someone's body. Temperature sensors in skin and internal organs monitor core temperature and transmit signals to control center situated in hypothalamus, a region of the brain. When core temperature falls below its set point, hypothalamus: 1. Sends more nerve impulses to blood vessels in skin that cause vessels to narrow that restricts blood flow to the skin, decreasing heat loss. 2. Stimulates skeletal muscles, causing brief bursts of muscular contraction, called shivering, that generates heat. When core temperature rises above its set point, hypothalamus: 1. sends fewer nerve impulses to blood vessels in the skin, causing them to dilate, that increases blood flow to skin and promotes heat loss. 2. Activates sweat glands and when sweat evaporates off skin surface it carries a large amount of body heat with it.