Download The atmosphere is 78% N2. All organisms need nitrogen to make

 The atmosphere is 78% N2.
 All organisms need nitrogen to make DNA and proteins.
 Most organisms cannot use the N2 in the atmosphere.
 A certain type of bacteria can “fix” nitrogen- which means
to break apart an N2 molecule and convert it into nitrogen
compounds that can be used by plants and other living
things.
 These nitrogen fixing bacteria can live in the soil or on the
roots of certain plants (in a symbiotic relationship.)
 Nitrogen is passed along the food chain and recycled by
decomposers.