The carbon cycle represents
circulation and recycling of chemical
element carbon in as a result of
action of living beings.

beings absorb carbon as
dioxide available in the
and the carbon atoms
part of glucose molecules.
the cellular respiration of
beings part of this material is
consumed to ATP and in this
carbon dioxide is returned
the atmosphere. The other is
incorporated by the
organisms into the molecules
compose their structure. The
atoms incorporated into the
are transferred to the trophic level
and again is liberated by the
respiration of the consumers,
becomes a constituent of
consumer body and part excreted as
uric acid urea (excretes later recycled
decomposer bacteria). Therefore
carbon by the producers in
returns to the
atmosphere cellular respiration
along the chain until the
decomposers also liberate carbon
dioxide their energetic metabolism.
Under conditions in a process
takes millions of years
incorporated into organisms may
constitute fossil fuels stored deposits
under the surface the planet; as fossil
burn the carbon atoms to
the atmosphere as dioxide or
carbon monoxide. of
vegetable fuels, like , also returns
carbon to atmosphere.