Name:______________________________
Nitrogen AND Carbon Cycles
Date: _________ Class: _______ Seat # ___
Nitrogen Cycle
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Nitrogen is a necessary _______________________ in the matter that makes up living things.
Even though the air contains __________________, (78%), most organisms
____________________ nitrogen gas in the air.
Nitrogen gas is called _________________ nitrogen because it is not combined with other
kinds of atoms.
Most organisms can use nitrogen only when it has been _______________ or combined with
other elements to form nitrogen- containing compounds, like ____________________.
The process of changing nitrogen gas into a usable form of nitrogen is called
___________________________.
Sometimes this can occur with __________________
Most nitrogen fixation, however, is performed by different kinds of __________________.
Some of these bacteria live in bumps called ___________________s on the roots of certain plants.
Once the ___________________have their nitrogen fixed, it can be used by
__________________ to build proteins and other complex substances.
Nitrogen Fixation
Nitrification
___________ + bacteria 1
+ bacteria 3
NH3 ____________ + bacteria2
__________________)
_____________________
Once N2 becomes a NITRATE, it is now in a form _________________ to the plant.
The plant will use it to make _________________ and amino acids to build its cells.
_______________________ that eat the plant will get the nitrogen to build their cells.
Animals that eat the _____________________ will get the nitrogen through them.
Nitrogen Recycled
 __________________ then return these nitrogen compounds in their ________________ and
when they ___________which are broken down by ___________________ in the form of
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ammonium ions.
Nitrifying bacteria change these ammonium ions ____________ into nitrites and nitrates.
__________________________ (Just like before)
Some will be ________________ by plants.
However, yet another type of _________________ break down the nitrogen compounds
completely _______________________ into N2. ______________
These bacteria then ________________free nitrogen, N2 back into the air, and the cycle starts again.
Carbon Cycle
 Carbon is the ____________________ for the matter that makes up the bodies of _________
living things.
 Producers take in carbon dioxide from the atmosphere during ________________________
 In this process, the producers use ___________________ from the carbon dioxide to produce
other carbon-containing molecules.
 These molecules include sugars –______________ (C6H12O6) and starches.
 Consumers obtain __________________from these molecules by breaking them down into
simpler molecules through the process called __________________________________.
 (Mighty, mighty mitochondrion)
 The consumers ________________ water and _____________________ as waste products of
the process.
 At the same time, producers release __________________ during photosynthesis.
 Other organisms, like us, ___________________________ from the atmosphere and use it in
their life processes and ____________________ carbon dioxide in __________________
Carbon dioxide from fuel
 Carbon, in the form of carbon dioxide, is also recycled in the environment when
_________________________, such as oil, coal, and natural gas, are burned.
 What problem is associated with the burning of fossil fuels? _______________________
Nitrogen AND Carbon Cycles
Nitrogen Cycle
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Nitrogen is a necessary building block in the matter that makes up living things.
Even though the air contains mostly nitrogen, (78%), most organisms cannot use nitrogen gas
in the air.
Nitrogen gas is called “free” nitrogen because it is not combined with other kinds of atoms.
Most organisms can use nitrogen only when it has been “fixed”: or combined with other
elements to form nitrogen- containing compounds, like NH3 or NO2
The process of changing nitrogen gas into a usable form of nitrogen is called nitrogen fixation.
Sometimes this can occur with lightning.
Most nitrogen fixation, however, is performed by different kinds of bacteria.
Some of these bacteria live in bumps called nodules on the roots of certain plants.
Once the producers have their nitrogen fixed, it can be used by
consumers to build proteins and other complex substances.
Nitrogen Fixation
Nitrification
N2 (gas) + bacteria 1
NH3 (ammonia) + bacteria2
+ bacteria 3
NO3 (nitrate)
NO2 ( nitrite)
Once N2 becomes a NITRATE, it is now in a form useable to the plant.
The plant will use it to make proteins and amino acids to build its cells.
Animals that eat the plant will get the nitrogen to build their cells.
Animals that eat the herbivores will get the nitrogen through them.
Nitrogen Recycled
 Consumers then return these nitrogen compounds in their wastes and when they die
which are broken down by decomposers in the form of ammonium ions.
 Nitrifying bacteria change these ammonium ions (NH3) into nitrites and nitrates.
(nitrification). (Just like before)
 Some will be used again by plants.
 However, yet another type of bacteria break down the nitrogen compounds completely
(denitrification) into N2. (gas)
 These bacteria then release free nitrogen, N2 back into the air, and the cycle starts again.
Carbon Cycle
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Carbon is the building block for the matter that makes up the bodies of ALL living
things.
Producers take in carbon dioxide from the atmosphere during photosynthesis.
In this process, the producers use carbon from the carbon dioxide to produce other
carbon-containing molecules.
These molecules include sugars –glucose (C6H12O6) and starches.
Consumers obtain energy from these molecules by breaking them down into simpler
molecules through the process called cellular respiration.
(Mighty, mighty mitochondrion)
The consumers release water and carbon dioxide as waste products of the process.
At the same time, producers release oxygen during photosynthesis.
Other organisms, like us, take in oxygen from the atmosphere and use it in their life
processes and exhale carbon dioxide in breathing.
Carbon dioxide from fuel
 Carbon, in the form of carbon dioxide, is also recycled in the environment when fossil
fuels, such as oil, coal, and natural gas, are burned.
 What problem is associated with the burning of fossil fuels? __global warming_________