LAB 2 nitrogen cycle Flashcards
what is the most oxidized state of nitrogen
Nitrate NO3-
what is the most reduced form of nitrogen
ammonia(NH3) or ammonium(NH4)
what is nitrogen a constituent of
Proteins, nucleic acids , ATP, membrane and cell walls (w out nitrogen is a useable form cells cannot live)
forms of organic nitrogen
from the breakdown of dead biomass to smaller organic molecules
forms of inorganic nitrogen
atmospheric nitrogen (N2)
Ammonia(NH3)
Nitrate (NO3-)
what is the goal of this lab
3 diffrent soil types will be tested for Ammonification, denitrification and Nitrogen fixation
what are the steps in the nitrogen cycle
Ammonification
nitrification
denitrification
Nitrogen fixation
What is ammonification
the degradation of nitrogenous proteins resulting in the release of ammonia which is initiated by extracellular enzymes(proteases) which work to hydrolyze the protein
Where ammonification is taking place there could be a pH increase from the ammonia which is being released
where was the starting point for ammonification in the lab when using the peptone and urea broth tubes?
we began with Peptones being the starting compound of ammonification in the lab
What is nitrification
oxidation of ammonia to nitrate in a bacterially mediated 2 step process
1) ammonia to nitrite via Nitrosomonas
2) Nitrite to nitrate via Nitrobacter
what is denitrification
an anaerobic process by which nitrates are reduced in to Nitrogen gas (reduction reaction)
Pseudomonas – nitrate to N2
E.coil– nitrite to nitrate
what is Nitrogen fixation
atmospheric nitrogen is converted into nitrogenous compounds(root nodules)
nitrogen is reduced into NH3 via the nitrogenase complex and is found in a broad rand of envoirments
the Nitrogenase enzyme complex
FeMon binds to N2 and reduces H and N2 to H2 and ammonia
the FeMon reveices the electron for this ozidation from ferredoxin which hydrolyzes ATP and reduces the FeMo protein
