Download combined with oxygen to form carbon dioxide.The energy that is

CS_Ch9_Environment
2/28/05
2:20 PM
Page 595
Activity 8 Photosynthesis, Respiration, and the Carbon Cycle
combined with oxygen to form carbon dioxide.The energy that is
released is either used by the organism (to move, digest food, excrete
wastes, etc.) or the energy may be lost as heat. In photosynthesis
energy is used to combine the carbon molecules from the carbon
dioxide, and oxygen is released.This is illustrated in the diagram. All
the energy comes from the Sun.The ultimate fate of all energy in
ecosystems is to be lost as heat. Energy does not recycle!
Bio Words
carbon cycle: the
process in which
carbon is passed from
one organism to
another, then to the
abiotic community,
and finally back to
the plants
However, inorganic nutrients do recycle.They are inorganic because
they do not contain carbon-carbon bonds.These inorganic nutrients
include the phosphorous in your teeth, bones, and cell membranes.
Also, nitrogen is found in your amino acids (the building blocks of
protein). Iron is in your blood.These are just a few of the inorganic
nutrients found in your body. Autotrophs obtain these inorganic
nutrients from the inorganic nutrient pool.These nutrients can usually
be found in the soil or water surrounding the plants or algae.These
inorganic nutrients
are then passed
THE CARBON
from organism to
CYCLE
atmospheric
carbon dioxide
organism as one
photosynthesis
animal
respiration
organism is
consumed by
another. Ultimately,
plan
exchange of CO2
respiration
all organisms die.
between atmosph
and water
They become
detritus, food for
burn
the decomposers.
At this stage, the
last of the energy is
extracted (and lost
as heat).The
inorganic nutrients
decay
are returned to the
decay
soil or water to be
taken up again.The
inorganic nutrients
carbon
are recycled; the
compounds
energy is not.
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Coordinated Science for the 21st Century