The human body maintains a relatively constant internal temperature (thermoregulation) through various physiological mechanisms controlled primarily by the hypothalamus in the brain When the body temperature rises, mechanisms are activated to dissipate heat One major mechanism is perspiration (sweating) Sweat glands secrete sweat onto the skin surface; the evaporation of this sweat absorbs heat from the body, thus cooling it down The "perspiration system" (sweat glands and associated neural control) is therefore a crucial part of the temperature control system for cooling The digestive system relates to nutrient processing, leg movement generates heat, and the ear is mainly for hearing/balance