Nitrogen oxides biochemical effects

Miyake, Y., and Wada, E. (1971) The isotope effect on the nitrogen in biochemical, oxidation-reduction reactions. Rec. Oceanogr. Works Jpn. 11, 1-6. 

Life as we know it would be impossible without the phenomenon of catalysis. Proteins (page 563) that catalyze biochemical reactions are called ENZYMES. Many industrial processes would also be impossible without catalysts, A CATALYST is a substance that increases the rate of a reaction but is recovered chemically unchanged at the end of the reaction. The catalyst enters into the chemical reaction, but is subsequently regenerated. Typical is the catalytic effect of nitrogen oxide on the rate... 

The chemical components of calcium carbonate — dissolved calcium ions and carbon dioxide — are widely distributed. Calcium is the fifth most common element in the earth s crust (after oxygen, silicon, aluminium and iron). It was extracted from early igneous rocks by the combined effects of erosion by the weather and corrosion by acidic gases (oxides of sulfur, oxides of nitrogen and carbon dioxide dissolved in rain water). Carbon dioxide makes up about 0.03 % by volume of the earth s atmosphere and is dissolved in both fresh and sea water. Combination of dissolved calcium ions and carbon dioxide resulted in the sedimentary deposition of calcium carbonate, which was subsequently converted into limestone rock. Early limestones (Precambrian — Table 2.1) are believed to have been deposited as precipitates of CaCOa, and/or as a result of the biochemical activity of very simple organisms, such as bacteria. 

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