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New Understanding of How Plants Use Water.
Plants naturally take in carbon dioxide they need for photosynthesis, the process of changing light energy to chemical energy. The carbon dioxide enters the plants through tiny holes or pores on the surface of leaves. However, each time a plant takes in one molecule of carbon dioxide gas, it loses hundreds of water molecules.
They say this suggests that changing plants to save more water will not affect plant growth. This method might be used to help engineer food crops that are resistant to extremely dry conditions.
The discovery could help farmers meet a growing demand for food as water supplies decrease.

http://www.voanews.com/specialenglish/2010-01-25-voa1.cfm

impression
I knew that I cannot live if there were not water and carbon dioxide and solar light to the creature of grass and the tree. I thought that the creature resembled a person. I am worried about the creature of the world whether I value life.