Thermoregulation

Humans are homeothermic animals whose body temperature is maintained roughly constant. They can generate heat independently and maintain the body temperature within a narrow range. Temperature changes in response to environmental exposure are controlled by maintaining the balance between the body’s heat gain and loss. These changes are detected by thermoreceptors in the body, and the information is transmitted to the thermoregulatory center, activating behavioral or autonomy control. Heat moves from within the body to the surface through blood flow and the respiratory system; it then moves from the body surface to the ambient environment and is dissipated. This is called heat loss. Heat production, which refers to the heat generated by food consumption or respiration, is the fuel for life activities, such as body temperature maintenance and muscle control. Body temperature generally refers to core body temperature, such as the axillary, oral, rectal, esophageal, and tympanic temperatures. The temperature displayed on the shell of the body is called the shell temperature and is specified as the skin temperature. Because the shell temperature is deeply involved in heat loss from the body surface, it fluctuates significantly with exposure to the ambient temperature. Thus, understanding the mechanisms of thermoregulation is important for maintaining or restoring normal body functions.