55-2-4

A small amount of the earth's water ends up in the living components of ecosystems. Roots of plants absorb some of this water ,most of which evaporates from plant leaves back into the atmosphere. Some combines eith carbon dioxide durning photosynthesis to produce high-energy organic compounds such as carbohydrates. Eventually these compounds are broken down in plant cells,which release water back into the environment. Consumers get their food or by drinking it.

地球上少量的水結束於生物組成的生態系統中，部份的水是由植物的根部吸收，多數是從植物的葉子經由蒸散作用蒸散到大氣中。一些以二氧化碳結合的化合物在光合作用期間製造出高能量的有機化合物，例如：碳水化合物。最後這些化合物在植物細胞中被分解，將水釋放回環境。消費者是以食物的攝取或以喝的方式獲得水分。

光合作用：6CO2+12H2O->6O2+C6H12O6+6H2O