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What Cycles?
Do you or your parents recycle newspapers,
aluminum cans, or plastic bottles?
Nature has its own recycling processes that are used to conserve
the resources it needs to keep ecosystems going. Matter constantly flows through the different
parts of an ecosystem. Remember
that the major components of an ecosystem include:
With the background knowledge of chemical cycles explained in Toxic or Not, we can now begin to understand how all the components of an ecosystem work together to maintain a constant supply of resources. The cycles of greatest importance involve water, carbon, oxygen, nitrogen, phosphorous, and sulfur. The Need for Energy Drives the Carbon Cycle
All
living things need energy. The
sun either directly or indirectly provides energy for most of the
organisms on earth. If the
sun provides energy, then why can’t we all just go lie out in the sun
to get an energy boost? In
addition to getting great tans, we would save money by eliminating the
need to buy food. It sounds great, but it can’t happen because our cells do
not contain chloroplasts, the site of photosynthesis in plant cells. Photosynthesis
may look like a large, intimidating word.
Let’s break it down in order to get a general idea of what it
means:
Plants use the energy contained in this sunlight to turn carbon dioxide into energy in the form of a carbohydrate (sugar) called glucose. Did you know that CO2 is pumped into sodas to make them fizzy (hence the name carbonated beverage). To summarize, photosynthesis involves two processes:
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