Location: 100md.com > knowledge > Text
.
Why do we perspire?

http://www.100md.com   2005-4-11 chinadaily

     Perspiration

    Why do we perspire?

    Notes:

    We perspire to maintain to keep the temperature of our internal thermostat set to an average, normal temperature of 98.6 degrees Fahrenheit. Our bodies come fully equipped with a temperature center in the brain, which consists of a control center, a heating center, and a cooling center.

    Our bodies use approximately 2,500 calories of our daily intake of calorie-laden food to fuel the body. This process, known as oxidation, burns the calories, producing enough heat to bring 25 quarts of water to the boiling point. Obviously, our bodies cannot tolerate this heat, which causes the temperature of the blood to rise dramatically, and the cooling center to springs into action.

    The cooling center slows the calorie burning process, and dilates, or opens, the blood vessels in the skin to release the excess heat, and the fluid known as perspiration.The release of this fluid cleanses the body, as it pours through our pores, which consist of millions of tiny openings in the skin. Perspiration emerges on the surface of the skin in the form of tiny, microscopic droplets, which quickly evaporate, and cool the body to its normal temperature.

    Evaporation of perspiration on humid days slows, and requires the assistance of manmade inventions, such as fans and air conditioners, to carry away the moist air, so our perspiration evaporates, and so our internal thermostat returns to it's normal setting of 98.6 degrees Fahrenheit. Apparently, our cooling center is not self-sufficient!

    perspire: 流汗

    thermostat: 自动调温装置

    oxidation: 氧化

    quarts: 夸脱

    dilates: 膨胀,扩大

    perspiration: 排汗

    pore: 毛孔

    microscopic: 用显微镜可见的

 
.