1. Why is NITROGEN Important?? Proteins and Amino Acids
Nitrogen is a KEY component in:
Chlorophyll
(Photosynthesis)
DNA (Nucleic Acids)
Proteins and Amino Acids

2. The atmosphere is made up of 78% Nitrogen gas (N2) but N2 is not useable by living things

3. Nitrogen Containing Molecules
NITRITE (NO2-)
Plants CAN’T use it
AMMONIA (NH3)
Some Plants CAN
use it
Nitrogen Containing Molecules
NITROUS OXIDES (NO)
Pollutants/Byproducts of burning fossil fuels
NITROGEN GAS (N2)
Plants CAN’T use it
NITRATE (NO3-)
Plants CAN use it

4. Processes that convert Nitrogen
AMMONIFICATION
Nitrogen in Dead organisms & Waste converted to Ammonium
-Bacteria, Decomposer, Fungi
NITROGEN
FIXATION
Nitrogen gas (N2) is converted to AMMONIA
-BACTERIA
-LIGHTNING
NITRIFICATION
Ammonia converted into Nitrites, then Nitrates
-Bacteria
Assimilation
 Nitrates used to make chlorphyll, amino acids, nucleic acids
-Plants
Processes that convert Nitrogen
DENITRIFICATION
Nitrates converted into N2
-Bacteria
BURNING FOSSIL FUELS (Combustion)
Creates Nitrous Oxides
-Humans
Fertilizer production
N2 converted into Ammonia
-Humans

5. Natural Fixation Human Fixation
N2 must be converted to form useable compounds. (Plants can only use Nitrogen when it’s combined with other elements)
Natural Fixation
“FIXING” NITROGEN
Human Fixation
LIGHTNING BACTERIA
FERTILIZER MANUFACTURING FOSSIL FUEL COMBUSTION

7. NITROGEN FIXATION
BACTERIA in soil and water FIX nitrogen gas from the atmosphere Nitrogen (N2) Ammonia (NH3)

8. BACTERIA ON THE ROOTS OF SOME PLANTS “FIX” NITROGEN GAS (N2).
ALFALFA
BACTERIA ON THE ROOTS OF SOME PLANTS “FIX” NITROGEN GAS (N2).
CLOVER
PEAS
LEGUMES.

9. N2 -------------NO2 and NO3 N2 -------------NH3
Nitrogen can be “FIXED” by LIGHTNING
(Energy splits N2, it reacts with O2 .
Nitrates dissolve in Water
absorbed by plant roots.)
N NO2 and NO3
(Nitrogen gas Nitrite and Nitrate)
When humans manufacture fertilizers we are “fixing” nitrogen
N NH3
(Nitrogen gas Ammonia)

10. What do these have in common??

11. Process that converts AMMONIA into NITRITES and NITRATES
Done by BACTERIA
NH3
Ammonia

12. ASSIMILATION: Plants absorb nitrates from the soil into their roots
ASSIMILATION: Plants absorb nitrates from the soil into their roots. Then the nitrogen gets used in amino acids, nucleic acids, and chlorophyll.

13. DENITRIFICATION-this process returns Nitrogen to the atmosphere
NITRATE NITROGEN GAS
(NO N2)
This is the opposite of Nitrification
“De”=opposite of

14. Ammonification: Part of the Decaying Process Nitrogen in dead organisms and waste into are converted into ammonia

15. Ammonification is done by 3 different organisms:1 2 3

16. You Practice!! With your partners, Properly identify each Phase of the Nitrogen Cycle On the next slide.

17. Bacteria convert Ammonia into Nitrates
DENITRIFICATION
Feeding
Animals Die or produce waste
FIXATION
ASSIMILATION
AMMONIFICATION
NITRIFICATION
Bacteria convert Ammonia into Nitrates

18. Nitrogen Cycle Video