The sweat pores allow loss of fluid as part of temperature control of the body. As a rise in external temerature is sensed by the nerve endings in the skin, the message is relayed to the hypothalmus, the temperature-regulating area of the brain. The brain then sends nerve impulses to the sweat glands stimulating them to release sweat until the skin receptors detect that the skin's temperature is back to normal. The brain then sends messages to stop the release of sweat.
