Questions tagged [nitrogen-cycle]
The nitrogen-cycle tag has no usage guidance.
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Why do animals excrete organic nitrogen compounds instead of N2 gas?
Protein metabolism produces ammonia, which needs to be disposed of; but oxidation of ammonia into water and dinitrogen produces energy, while creating urea or uric acid consumes energy, and excreting ...
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Bacterium fixed nitrogen transfer mechanism
As it is well known, Rhizobium and other bacteria have the capacity to fix Nitrogen and thus perform a crucial role in the natrual nitrogen cycle.
I am trying to find a reliable source on how the ...
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Why does nitrification -oxidation consume organic matter?
I want to express some doubts regarding autotroph bacteria.
The question I want to ask is relative to wastewater treatment plants, more precisely at the nitrification/denitrification step.
I've ...
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Nitrate fertilizer problem
Take the above problem. I understand how to do the calculation. However I can't seem to understand the units of the answer in the calculation.
The answers illustrate the units as t/ha^-2 which is ...
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Why do bacteria denitrify?
Denitrification is the microbial respiration in anoxic condition. If the process is complete we have :
$$2 \text{NO}_3^{-} + 10 \text{e}^{-} +12\text{H}^+ \rightarrow \text{N}_2 + 6 \text{H}_2\text{O}$...
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In this aquponic tank, what are these three plants and could they be killing my beta fish?
I have a small aquaponic fish tank. In the tank there are two unknown types of water plants from a local pet store and the top there are three air plants from a local garden center. This tank was ...
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How does free living nitrogen fixing bacteria fix N2 in aerobic condition?
If a Azotobacter is free living nitrogen fixer it will also require ATP through cellular respiration. I am confused here: if Nitrogenase is highly sensitive to oxygen molecule how will Azotobacter be ...
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What is the energetic costs in KJ/g NH3 for nitrogenase fixation
What is the energetic costs in KJ/g NH3 for nitrogenase fixation.
I want to compare Haber-Bosch vs nitrogenase.
How would I force the biological stochiometry of 8e- electrons into an energy quantity.
$...
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Will ammonia continue to accumulate in an aquarium tank if a strong antibacterial or chlorine is added to the water?
I've always wondered what would happen if dead plants and fecal matter lay in chlorinated waters and/or waters treated with strong antibacterials or antibiotics.
I've heard that aquarium tanks ...
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In biological nitrogen fixation, the electrons required to reduce dinitrogen to ammonia are provided by which compound? [closed]
The reaction is as follows:
N2 + 16ATP + 8e- + 8H+ → 2NH3 + H2 + 16ADP + 16Pi
From where are the 8 electrons coming from?
We know that in photosynthesis, the electrons are supplied by the oxidation ...
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Why is urea not converted to ammonia in the body?
After the liver processes metabolites to produce urea and other by-products, these travel in the blood to the heart, then they are oxygenated, and some travel through the renal artery to the kidneys.
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Difference between bacteria and bacteroids?
During nodule formation Rhizobium is converted to bacteroids. What's the difference between them?
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Why do soil bacteria produce nitrous oxide as a result of anhydrous ammonia fertilizer application?
The NPR article and 4 minute audio news item Can Anyone, Even Walmart, Stem The Heat-Trapping Flood Of Nitrogen On Farms? discusses unexpected contributions of greenhouse gasses from the manufacture ...
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Recycling and storage of nitrogen from breakdown of macromolecules?
If nitrogen is so important (it's a constituent of both proteins and nucleic acids), why are animals still throwing them out, and needing to eat it again? Is it true that in almost a billion years of ...
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Why do organisms excrete nitrogenous wastes?
Organisms excrete nitrogenous wastes in the form of urea, uric acid or ammonia. But isn’t that a bit of a waste? There is a shortage of biologically available nitrogen in the ecosystem, and plants ...
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