Search results
Results From The WOW.Com Content Network
Nitrogen is a fundamental chemical component of amino acids, the molecular building blocks of protein. As such, nitrogen balance may be used as an index of protein metabolism. [1] When more nitrogen is gained than lost by an individual, they are considered to have a positive nitrogen balance and be in a state of overall protein anabolism.
The cell cycle is a series of complex, ordered, sequential events that control how a single cell divides into two cells, and involves several different phases. The phases include the G1 and G2 phases, DNA replication or S phase, and the actual process of cell division, mitosis or M phase. [1]
The isolated reaction of anabolism is unfavorable in a cell due to a positive Gibbs free energy (+ΔG). Thus, an input of chemical energy through a coupling with an exergonic reaction is necessary. [ 1 ] : 25–27 The coupled reaction of the catabolic pathway affects the thermodynamics of the reaction by lowering the overall activation energy ...
The process of nitrogen fixation requires an influx of energy in the form of adenosine triphosphate. Nitrogen fixation is highly sensitive to the presence of oxygen, so Azotobacter developed a special defensive mechanism against oxygen, namely a significant intensification of metabolism that reduces the concentration of oxygen in the cells. [ 40 ]
Utilizing a large amount of metabolic energy and the enzyme nitrogenase, some bacteria and cyanobacteria convert atmospheric N 2 to NH 3, a process known as biological nitrogen fixation (BNF). [4] The anthropogenic analogue to BNF is the Haber-Bosch process, in which H 2 is reacted with atmospheric N 2 at high temperatures and pressures to ...
Anammox, an abbreviation for "anaerobic ammonium oxidation", is a globally important microbial process of the nitrogen cycle [1] that takes place in many natural environments. The bacteria mediating this process were identified in 1999, and were a great surprise for the scientific community. [ 2 ]
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.
Denitrification is commonly used to remove nitrogen from sewage and municipal wastewater. It is also an instrumental process in constructed wetlands [28] and riparian zones [29] for the prevention of groundwater pollution with nitrate resulting from excessive agricultural or residential fertilizer usage. [30]