THE EXAMS POINTNitrogen: follow the transformations
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Nitrogen: follow the transformations
01 · Atmospheric N₂ → fixed nitrogen
Biological fixation converts N₂ to ammonia/ammonium forms; fixation is not nitrification.
02 · Ammonium → nitrite → nitrate
Nitrification is oxidation carried out by microorganisms.
03 · Plant assimilation
Plants incorporate absorbed nitrogen into organic molecules.
04 · Organic nitrogen → ammonium
Ammonification returns reduced inorganic nitrogen during decomposition.
05 · Nitrate → N₂
Denitrification returns nitrogen to the atmosphere under suitable conditions.
Connect the branches
These are connected pathways, not a single compulsory route for every nitrogen atom.
Avoid the exam trap
Plants do not generally assimilate atmospheric N₂ directly; symbiotic microbes carry out fixation.
Test yourself: Which process converts ammonium to nitrite and nitrate?
Nitrification; it is distinct from nitrogen fixation and ammonification.
A concise revision aid with simplified connections. It supports the full chapter and primary references; it does not replace them.