Photosynthesis is a process which uses the energy of sunlight to convert carbon dioxide from the air into sugars. These sugars are subsequently transformed into other matter. They are the material and energetic basis of most organisms on earth, in particular of us humans. (Sure, there are some organisms living independently from sunlight. They are populating deep soil layers and the deep sea and they are more abundant than previously thought. This is not significant in terms of human nutrition, however. Our bodies – and the bodies of the organisms we are eating – are built 100% from sunlight and most of our bodies carbon comes from photosynthetic sugars.) In addition, photosynthesis is the process, which produces all the oxygen we are breathing, which has produced all those fossil fuels we are happily combusting and which eliminates all the carbon dioxide we are producing. (Well, unfortunately not precisely all of it.)
The following picture is meant to symbolize the process of photosynthesis. I leave it to your consideration, whether this has succeeded. (One clear shortcoming is the fact that it does not give any indication of the global importance of photosynthesis…)
Photosynthesis
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