PHENOMENA AND PROCESSES Chemical Phenomena [G02] Chemical Phenomena Biochemical Phenomena [G02.111] Biochemical Phenomena Acid-Base Equilibrium [G02.111.007] Acid-Base Equilibrium Acylation [G02.111.012] Acylation Aerobiosis [G02.111.017] Aerobiosis Agglutination [G02.111.026] Agglutination Alkylation [G02.111.035] Alkylation Allosteric Regulation [G02.111.044] Allosteric Regulation Amination [G02.111.053] Amination Anaerobiosis [G02.111.062] Anaerobiosis Autotrophic Processes [G02.111.071] Autotrophic Processes Base Composition [G02.111.080] Base Composition Binding, Competitive [G02.111.084] Binding, Competitive Biocatalysis [G02.111.086] Biocatalysis Biomineralization [G02.111.092] Biomineralization Biosynthetic Pathways [G02.111.098] Biosynthetic Pathways Biotinylation [G02.111.109] Biotinylation Body Composition [G02.111.130] Body Composition Brain Chemistry [G02.111.150] Brain Chemistry Carbohydrate Metabolism [G02.111.158] Carbohydrate Metabolism Citric Acid Cycle [G02.111.165] Citric Acid Cycle Cyclization [G02.111.180] Cyclization Dealkylation [G02.111.188] Dealkylation Deamination [G02.111.192] Deamination Decarboxylation [G02.111.195] Decarboxylation DNA Cleavage [G02.111.210] DNA Cleavage DNA Methylation [G02.111.218] DNA Methylation DNA Repair [G02.111.222] DNA Repair DNA Replication [G02.111.225] DNA Replication Down-Regulation [G02.111.240] Down-Regulation Electron Transport [G02.111.248] Electron Transport Energy Transfer [G02.111.255] Energy Transfer Enzyme Activation [G02.111.263] Enzyme Activation Esterification [G02.111.270] Esterification Halogenation [G02.111.323] Halogenation Heterotrophic Processes [G02.111.375] Heterotrophic Processes Hydrogenation [G02.111.380] Hydrogenation Hydroxylation [G02.111.385] Hydroxylation Kinetics [G02.111.490] Kinetics Lipid Peroxidation [G02.111.515] Lipid Peroxidation Lipogenesis [G02.111.528] Lipogenesis Lipolysis [G02.111.534] Lipolysis Lipoylation [G02.111.540] Lipoylation Melanogenesis [G02.111.545] Melanogenesis Membrane Fluidity [G02.111.550] Membrane Fluidity Molecular Mimicry [G02.111.560] Molecular Mimicry Molecular Structure [G02.111.570] Molecular Structure Nitrogen Cycle [G02.111.587] Nitrogen Cycle Anaerobic Ammonia Oxidation [G02.111.587.125] Anaerobic Ammonia Oxidation Denitrification [G02.111.587.250] Denitrification Nitrification [G02.111.587.500] Nitrification Nitrogen Fixation [G02.111.587.750] Nitrogen Fixation Nitrosation [G02.111.595] Nitrosation Nucleic Acid Denaturation [G02.111.603] Nucleic Acid Denaturation Nucleic Acid Hybridization [G02.111.611] Nucleic Acid Hybridization Nucleic Acid Renaturation [G02.111.619] Nucleic Acid Renaturation Osmoregulation [G02.111.635] Osmoregulation Osmosis [G02.111.655] Osmosis Peptide Biosynthesis [G02.111.660] Peptide Biosynthesis Phosphorylation [G02.111.665] Phosphorylation Phototrophic Processes [G02.111.669] Phototrophic Processes Prenylation [G02.111.672] Prenylation Protein Aggregation, Pathological [G02.111.675] Protein Aggregation, Pathological Protein Binding [G02.111.679] Protein Binding Protein Folding [G02.111.688] Protein Folding Protein Modification, Translational [G02.111.691] Protein Modification, Translational Protein Multimerization [G02.111.694] Protein Multimerization Protein Stability [G02.111.700] Protein Stability Proteolysis [G02.111.720] Proteolysis Proteostasis [G02.111.730] Proteostasis RNA Cleavage [G02.111.740] RNA Cleavage RNA Folding [G02.111.750] RNA Folding RNA Processing, Post-Transcriptional [G02.111.760] RNA Processing, Post-Transcriptional RNA Replication [G02.111.770] RNA Replication RNA Stability [G02.111.780] RNA Stability Sequence Homology [G02.111.810] Sequence Homology Signal Transduction [G02.111.820] Signal Transduction Structure-Activity Relationship [G02.111.830] Structure-Activity Relationship Substrate Cycling [G02.111.833] Substrate Cycling Substrate Specificity [G02.111.835] Substrate Specificity Transcription, Genetic [G02.111.873] Transcription, Genetic Up-Regulation [G02.111.905] Up-Regulation PHENOMENA AND PROCESSES Chemical Phenomena [G02] Chemical Phenomena Organic Chemistry Phenomena [G02.607] Organic Chemistry Phenomena Acylation [G02.607.063] Acylation Alkylation [G02.607.094] Alkylation Amination [G02.607.110] Amination Carbon Cycle [G02.607.125] Carbon Cycle Cyclization [G02.607.133] Cyclization Dealkylation [G02.607.141] Dealkylation Deamination [G02.607.157] Deamination Decarboxylation [G02.607.188] Decarboxylation Esterification [G02.607.250] Esterification Glycosylation [G02.607.299] Glycosylation Hydrogenation [G02.607.324] Hydrogenation Hydroxylation [G02.607.348] Hydroxylation Isomerism [G02.607.445] Isomerism Maillard Reaction [G02.607.522] Maillard Reaction Nitrogen Cycle [G02.607.560] Nitrogen Cycle Anaerobic Ammonia Oxidation [G02.607.560.125] Anaerobic Ammonia Oxidation Denitrification [G02.607.560.250] Denitrification Nitrification [G02.607.560.500] Nitrification Nitrogen Fixation [G02.607.560.750] Nitrogen Fixation Nitrosation [G02.607.598] Nitrosation Oxidative Coupling [G02.607.765] Oxidative Coupling Phosphorylation [G02.607.780] Phosphorylation PHENOMENA AND PROCESSES Biological Phenomena [G16] Biological Phenomena Ecological and Environmental Phenomena [G16.500] Ecological and Environmental Phenomena Air Ionization [G16.500.050] Air Ionization Anthropogenic Effects [G16.500.075] Anthropogenic Effects Biofouling [G16.500.100] Biofouling Carbon Cycle [G16.500.150] Carbon Cycle Climatic Processes [G16.500.175] Climatic Processes Coral Bleaching [G16.500.188] Coral Bleaching Cosmic Radiation [G16.500.200] Cosmic Radiation Environment [G16.500.275] Environment Eutrophication [G16.500.285] Eutrophication Geologic Sediments [G16.500.320] Geologic Sediments Meteorological Concepts [G16.500.750] Meteorological Concepts Nitrogen Cycle [G16.500.768] Nitrogen Cycle Anaerobic Ammonia Oxidation [G16.500.768.125] Anaerobic Ammonia Oxidation Denitrification [G16.500.768.249] Denitrification Nitrification [G16.500.768.500] Nitrification Nitrogen Fixation [G16.500.768.600] Nitrogen Fixation Ocean Acidification [G16.500.777] Ocean Acidification Ozone Depletion [G16.500.785] Ozone Depletion Refugium [G16.500.819] Refugium Rhizosphere [G16.500.853] Rhizosphere Soil Erosion [G16.500.870] Soil Erosion Steam [G16.500.887] Steam Water Cycle [G16.500.943] Water Cycle Water Movements [G16.500.971] Water Movements Wildfires [G16.500.980] Wildfires PUBLIC HEALTH Environmental Health [SP4] Environmental Health Environment [SP4.606] Environment Chemical Phenomena [SP4.606.635] Chemical Phenomena Biogeochemical Cycle [SP4.606.635.251] Biogeochemical Cycle Carbon Cycle [SP4.606.635.251.224] Carbon Cycle Phosphorus Cycle [SP4.606.635.251.455] Phosphorus Cycle Nitrogen Cycle [SP4.606.635.251.567] Nitrogen Cycle Denitrification [SP4.606.635.251.567.309] Denitrification Nitrification [SP4.606.635.251.567.562] Nitrification

Nitrogen Cycle - Preferred

Concept UI	M0542469
Scope note	The circulation of nitrogen in nature, consisting of a cycle of biochemical reactions in which atmospheric nitrogen is compounded, dissolved in rain, and deposited in the soil, where it is assimilated and metabolized by animals, plants, bacteria, and fungi, eventually returning to the atmosphere by bacterial decomposition of organic matter.
Preferred term	Nitrogen Cycle
Entry term(s)	Cycle, Nitrogen Cycles, Nitrogen Nitrogen Cycles

Ammonification - Narrower

Concept UI	M000746997
Preferred term	Ammonification