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Where Carbon Goes

Not all carbon molecules are released into the atmosphere as carbon dioxide.  Most carbon molecules remain stored in the body.  Carbon molecules stored in an organism's body do not get recycled in an ecosystem until an organism dies.  Bacteria and fungi get their energy by decomposing dead organic matter.  The process of decomposition releases carbon dioxide back into the atmosphere.  

Some dead organic material does not get decomposed.  Instead, it turns into fossils.  Some dead organic matter can eventually turn into oil and coal.  The burning of oil and coal for energy needs is another method of releasing carbon dioxide.   

Large reserves of methane hydrates are found within the earth. These are molecules of methane gas (one carbon and 4 hydrogens - in center of photo at right) that embedded in a complex of water (red and white balls).  This is a major potential source of energy and scientists are studying how to tap it. Click here for more. 

Plants do not make carbon dioxide, so they have to get it from the surrounding atmosphere.  Carbon dioxide gets released into the atmosphere only after the carbon compounds, made by plants, get broken down for energy.  Thus, the driving force for the carbon cycle is the need for organisms to acquire energy.

If plants make sugar from carbon dioxide, then shouldn’t we try to provide the atmosphere with as much carbon dioxide as we can by constantly burning fossil fuels?  How could too much carbon dioxide in the atmosphere cause any problems? 

Plants are only able to use a certain amount of carbon dioxide at one time.  Any extra carbon dioxide will simply remain in the atmosphere.  The extra carbon dioxide absorbs heat released from the earth.  The trapping of heat can raise the overall temperature of the earth producing a greenhouse effect (click here to read about Global Warming). 

Excess carbon dioxide gets into the atmosphere by humans who burn carbon-containing molecules.  How many examples of this can you list?

Today there is great interest in finding alternative energy sources, especially from wind and sun. Click here to see a good summary of ways to get energy other than burning carbon.


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