Elements in living matter

A very small amount of the matter in the earth s crust, oceans, and atmosphere is involved in living matter. The main element in living matter is carbon, but only a tiny... 

Calcinm is an essential element in living matter. It is the major component of bones and teeth the calcinm ion is present in a complex phosphate salt, hydroxyapatite, Ca5(P04)30H. A characteristic fnnction of Ca ions in living systems is the activation of a variety of metabolic processes. Calcium plays a vital role in heart action, blood clotting, mnscle contraction, and nerve impulse transmission. 

A very small amount of the matter in the earth s crust, oceans, and atmosphere is involved in living matter. The main element in living matter is carbon, but only a dny fraction of the carbon in the environment occurs in living organisms. More than one-quarter of the total mass of the earth s crust, oceans, and atmosphere is made up of silicon, yet it has almost no biological role. 

Phosphorus acts as an essential element in living matter in a number of functions associated with the structure of compounds containing this element. They are mainly structural functions, functions in energy metabolism and activation, regulatory and catalytic functions. 

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. 

The main biochemical reactions coupled with energy transport and incorporation of chemical elements into living matter are shown in Table 1. 

All forms of matter are composed of one or more elements. Be able to list the major elements in living things. 

To include living matter and the minerals in the sea would scarcely affect our figures. The elements in living things and in the sea were ultimately derived from the earth s hard crust. 

Many elements are present in living matter in very small amounts, but they are nevertheless essential. Here, for example, are the results of growing identical plants in soil without phosphorus and in soil containing a normal amount of phosphorus. 

Sodium and potassium are essential elements of living matter. Sodium ions and potassium ions are present in intracellular and extracellular fluids, and they are essential for osmotic balance and enzyme functions. We now describe the preparations and uses of several of the important compounds of sodium and potassium. 

Although it constimtes only about 0.09 percent by mass of Earth s crust, carbon is an essential element of living matter. It is found free in the form of diamond and graphite (see Figure 8.17), and it is also a component of natural gas, petroleum, and coal. (Coal is a natural dark-brown to black solid used as a fuel it is formed from fossilized plants and consists of amorphous carbon with various organic and some inorganic compounds.) Carbon combines with oxygen to form carbon dioxide in the atmosphere and occurs as carbonate in limestone and chalk. 

The list of elements found in living matter is very different from that for earth s crust, as shown in the Top Ten. Oxygen, carbon, hydrogen, and nitrogen form the basis for all biologically important molecules. Some elements found in the body (called trace elements) are crucial for life, even though they are present in relatively small amounts (Table 3.2). 

At first, he thought that the situation with the isotopes would be analogous to the situation with the homochirality of biological macromolecules he expected that all chemical elements of living matter would be pure isotopes and not mixtures of isotopes. An organism has the possibility to choose between the diverse isotopes. In 1928 Vernadsky started experiments in order to prove this hypothesis. However both his own experiments and the experiments of other scientists did not give decisive results. 

The list of elements found in living matter is very different from those of the Earth s crust, oceans, and atmosphere. The major elements in living organisms are shown in Table 3.2. 

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