Living matter elements

Nitrogen is an essential constituent of all living matter, being one of the elements present in proteins. Proteins are synthesised by... 

Properties Oxygen is a colorless, odorless, and tasteless gas, that makes up about 21% of the Earth s atmosphere. It is essential to life for almost all living matter. It is found in nature in combination with all elements except the so-called rare gases (helium, argon, and neon). It can be liquefied under pressure. 

Phosphorus is an essential element present in all living matter and is vital in biological and ecological processes. It occurs in DNA and other nucleic acids, and in bones. 

A comparison of carbon-element bonds (C—El) inside the most important structural frameworks of living matter (and of the most important drugs) with the corresponding silicon-element bonds (Si—El) is given in Table 1. 

It has been proposed that there may be a close link between the amount of an element available to living matter and the fraction of the total content which is labile (with the lability value being loosely defined as the total, accessible, hydrated ion level). Either the whole or part of the analytical result may be derived from dissociation of labile complex ions or dissolution of moderately soluble compounds. If one or both of these two processes proceed at a relatively slow rate, the magnitude of the lability value becomes time dependent . Conversely, if a complex exchanges ligands fairly rapidly, the amount present in... 

It is somewhat difficult to define what is meant by a toxic element. Some elements, such as white phosphorus, chlorine, and mercury, are quite toxic in the elemental state. Others, such as carbon, nitrogen, and oxygen, are harmless as usually encountered in their normal elemental forms. But, with the exception of those noble gases that do not combine chemically, all elements can form toxic compounds. A prime example is hydrogen cyanide. This extremely toxic compound is formed from three elements that are nontoxic in the uncombined form, and produce compounds that are essential constituents of living matter, but when bonded together in the simple HCN molecule constitute a deadly substance. 

Nitrogen occurs in nature where it constitute nearly three fifth of the earth s atmosphere. It also occurs in the combined form as nitrates. Nitrogen is an essential element for living matter because it is an important constituent of proteins and even human body. Phosphorus is also essential for life because its compound control almost all biological processes. 

Proteins constitute the largest portion of living matter in all types of cells. They serve as structural elements in cells and tissues, show specific catalytic activity, function as enzymes, and are found in cell membranes. Most IR and classical Raman studies focus on the characterization of protein secondary structures by using sets of absorption bands and diffusion Raman lines reflecting especially the motions of peptide groups (Sec. 

Hydrogen, the first element in the periodic table, is unique it has no congeners. It is a very widely distributed element. It is found in most of the substances which constitute living matter, and in many inorganic substances. There are more compounds of hydrogen known than of any other element, carbon being a close second. Its most important compound is water, HgO. 

Circulation Rates of Elements. The concept of cycling of individual elements, in part coupled to the hydrologic cycle, has been developed and quantified over the past half century. Besides the total quantities of the elements present in various reservoirs—bedrock (the lithosphere), soils, all forms of living matter (the biosphere), the oceans, the atmosphere, and fresh water—the rates of exchange and mechanisms of movement from one reservoir to another are considered in the cycle. This concept is highly relevant in developiog a frame of reference for evaluating possible environmental... 

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