Читать книгу Biochemistry For Dummies - John Moore T., Richard Langley H., John T. Moore - Страница 17

Specific heat is the amount of heat required to increase the temperature of a gram of water by 1 degree Celsius. The high specific heat of water means that changing the temperature of water isn’t easy. Water also has a high heat of vaporization, the quantity of heat required at a specified temperature to convert a specified mass of liquid into vapor. Humans can rid their bodies of a great deal of heat when their sweat evaporates from their skin, making sweat a very effective cooling method. We’re sure you’ll notice this cooling effect during your biochem exams.

Because of water’s high specific heat and heat of vaporization, lakes and oceans can absorb and release a large amount of heat without a dramatic change in temperature. This give-and-take helps moderate the Earth’s temperature and makes it easier for an organism to control its body temperature. Warm-blooded animals can maintain a constant temperature, and cold-blooded animals — including lawyers and some chemistry teachers — can absorb enough heat during the day to last them through the night.