What Is Carbon?
An element (C)
The basis of life of earth
Found in rocks, oceans, atmosphere
The same carbon atoms are used
repeatedly on earth. They cycle between
the earth and the atmosphere.
Plants Use Carbon Dioxide
Plants pull carbon dioxide from the
atmosphere and use it to make food –—
The carbon becomes part of the plant
Animals Eat Plants
When organisms eat plants, they take in
the carbon and some of it becomes part
of their own bodies.
Plants and Animal Die
When plants and animals die, most of
their bodies are decomposed and
carbon atoms are returned to the
Some are not decomposed fully and end
up in deposits underground (oil, coal,
Carbon Slowly Returns to Atmosphere
Carbon in rocks and underground
deposits is released very slowly into the
This process takes many years.
Cycle – Repeats Over and
Over and Over and Over …
Carbon Cycle Diagram
Carbon in Atmosphere
carbon to make
break down dead
part of oil or
Fossil fuels are
is returned to
Carbon in Oceans
Additional carbon is stored in the ocean.
Many animals pull carbon from water to use in
Animals die and carbon substances are
deposited at the bottom of the ocean.
Oceans contain earth’s largest store of carbon.
Fossil fuels release carbon stores very
Burning anything releases more carbon
into atmosphere — especially fossil fuels
Increased carbon dioxide in atmosphere
increases global warming
Fewer plants mean less CO2 removed
What We Need to Do
Burn less, especially fossil fuels
Promote plant life, especially trees
•Good News: Air is 78% nitrogen.
•Bad News: Organisms cannot use pure nitrogen.
•How is the problem “fixed”? It must be combined with other elements into a usable form.
Combine nitrogen with
other elements to make it
usable by organisms
Break down nitrogen
compounds in waste and
dead organisms so it can
be returned to the soil
Break down nitrogen
compounds in the soil
and release back into
Lightning also fixes
nitrogen by combining
it with oxygen. It then
falls down with rain in
a usable form.
Blue Arrows –
Red Arrows –