The chemical composition of living organisms. The chemical composition of living organisms from the point of view of science What does the chemical composition of living organisms testify to
The basis of living things is made up of two classes of chemical compounds - squirrels and nucleic acids. Moreover, in living organisms, unlike inanimate matter, these compounds are characterized by the so-called chiral purity. In particular, squirrels built only on the basis of left-handed (polarizing light to the left) amino acids, a nucleic acids consist exclusively of dextrorotatory sugars. This chiral purity developed at the very initial stages of the evolution of living matter. It is believed that the minimum time of the global transition from complete chaos to chiral purity is from 1 to 10 million years. Consequently, in this sense, the origin of life could have occurred on Earth relatively instantaneously over a period of time 5,000 times less than the estimated age of the planet.
Squirrels are responsible primarily for the metabolism and energy in a living system, i.e. for all the reactions of synthesis and decay that take place in any organism from birth to death. Nucleic acids provide the ability of living systems to reproduce themselves. They are the basis of the matrix, the amazing "invention" of nature. The matrix represents a kind of blueprint, i.e., a complete set of information on the basis of which species-specific protein molecules are synthesized.
In addition to proteins and nucleic acids, living organisms include lipids (fats) , carbohydrates and very often vitamin C .
Many chemical elements present in the environment have been found in living systems, but only about 20 of them are necessary for life. These elements are called biogenic. On average, about 70% of the mass of organisms is oxygen , 18% - carbon , 10% - hydrogen(substances-organogens). Next come nitrogen , phosphorus , potassium , calcium , sulfur , magnesium , sodium , chlorine ,iron. These so-called universal biogenic elements, present in the cells of all organisms, are often called macronutrients .
Some elements are found in organisms in extremely low concentrations (not higher than a thousandth of a percent), but they are also necessary for normal life. These are biogenic trace elements. Their functions and roles are very diverse. Many trace elements are part of the series enzymes , vitamins , respiratory pigments, some affect growth, development rate, reproduction, etc.
The presence in the cells of a number of elements depends not only on the characteristics of the organism, but also on the composition of the environment, food, environmental conditions, in particular, on the solubility and concentration of salts in the soil solution. A sharp deficiency or excess of biogenic elements leads to abnormal development of the organism or even to its death. Additives of biogenic elements to the soil to create their optimal concentrations are widely used in agriculture.
Mineral elements, also called bioelements, play an important role in the human body: they are a building material (calcium, phosphorus, iron); regulate many biochemical processes during metabolism (potassium, sodium, iodine, chlorine, copper, manganese, selenium and others); take part in the process of blood coagulation (calcium); maintain the body's water balance (sodium, potassium); affect the preservation of acid-base balance; are part of enzymes (enzymes). Bioelements are divided into two groups: Macronutrients present in large quantities in food (up to several percent of dry weight) and necessary for the body in specific weight quantities for its proper functioning. Trace elements required by the body in trace amounts (of the order of 10-2 to 10-11% of the body's live weight). They are very important for metabolic processes and the production of hormones and enzymes.
(additionally more material) All living organisms selectively relate to the environment. The composition of the chemical elements of living systems differ from the chemical elements of the earth's crust. In the earth's crust O, Si, Al, Na, Fe, K, in living organisms H, O, C, N. All other elements less than 1%. In any living organism, you can find all the elements of the environment, however, in different quantities. However, this does not mean that they are necessary. 20 chemical elements are needed - those without which a living system cannot do. Depending on the environment and metabolism, the set of these substances is different. Some chemical elements are part of all living organisms (universal chemical elements) H, C, N, O. Na, Mg, P, S, Ca, K, Cl, Fe, Cu, Mn, Zn, B, V, Si, co, Mo. Silicon is part of mucopolysaccharides of connective tissue.
The composition of living organisms includes 4 elements that are surprisingly suitable for performing the functions of a living thing: O, C, H, N. They share the common property that they readily form covalent bonds through electron pairing. C atoms have the property that they can combine into long chains and rings, with which other chemical elements can bind. There are a lot of C connections. Silicon is closest to carbon, but C forms CO2, which is widespread in nature and available to everyone, and silicon oxide is an element of sand (insoluble).
Macromolecules - nucleic acids, proteins, polypeptides, lipids, polysaccharides - polymers formed by monomers connected by covalent bonds. Any living organism is 90% composed of 6 chemical elements - C, O, H, P, N, S - bioelements(biogenic elements).
Cell
All living organisms use common materials for life. About 120 are used (20 amino acids, 5 nitrogenous bases, 4 classes of lipids, small molecules - simple acids, water, phosphates - 70). These are products of chemical evolution (organic compounds of living systems and components of inanimate matter).
Like biochemistry. As we already know, all living organisms are made up of cells. Cells, in turn, are made up of chemical elements. The chemical elements without which life on Earth would not be possible are called nutrients.
Biogenic elements are chemical elements, which are part of the cells of the body, as well as those elements without which the vital activity of cells is impossible: organic and inorganic substances, polymeric and low molecular weight. Each of us knows from childhood that more than half of a person consists of water. Accordingly, the first and most important biogenic substance is water.
The main chemical elements of organisms:
- hydrogen;
- oxygen;
- phosphorus;
- sulfur;
- nitrogen;
- carbon.
inorganic compounds in living organisms:
- carbonates;
- phosphates;
- ammonium salts;
- sulfates.
Other biogenic elements include: nonmetals:
1) Iodine and iodine compounds are very important for the body, play a big role in metabolic processes. Iodine is part of thyroxine, a thyroid hormone.
2) Chlorine. The anions of this element maintain the saline environment of the body at a level necessary for proper functioning. Also included in some organic compounds.
3) Silicon. Included in the ligaments and cartilage (orthosilicic acid), serves as a binder in some polysaccharide chains.
4) Selenium and its derivatives. They are part of some enzymes (selenocysteine).
Other organic substances that make up a living organism:
- Acetic aldehyde;
- Acetic acid;
- Ethanol is a product and substrate of biochemical reactions.
Equally important are the following connections:
HEM is a compound of iron with a paraffin molecule;
Cobalamin is a cobalt compound (vitamin B12).
calcium and magnesium- base metals, which, along with iron most commonly found in biological systems. Magnesium and its ions play an important role for the functioning of the cell, more precisely, ribosomes and protein synthesis in the cell. Magnesium is also part of chlorophyll. Calcium in a living organism can be present in the form of insoluble salts:
- calcium carbonate- the substance of which mollusk shells are composed;
- calcium phosphate- participates in the construction of the skeleton.
The composition of enzymes includes many metals of the 4th period of the periodic system:
1) Iron is involved in the process of saturation of cells with oxygen, being part of hemoglobin.
2) Zinc ions found in almost all enzymes.
3) Manganese It is also part of some enzymes, but plays a more important role in maintaining a normal external biosphere: it ensures the release of oxygen into the atmosphere, and also participates in the photochemical restoration of water.
4) Molybdenum is an integral part of nitrodinase, an enzyme of nitrogen-fixing bacteria, which helps to restore nitrogen from the outside to ammonia.
5) Cobalt- as we have already said, is part of cobalamin or vitamin B12.
Low molecular weight compounds that are part of living organisms:
- Amino acids- They are made up of proteins.
- Mono and aligosaccharides- They make up the structural tissues of organisms.
- Nucleamides They are made up of nucleic acids.
- Lipids- components of cell membranes.
There are also many other substances that are actively involved in the life of living organisms: coenzymes, terpenes and many others.
Let's highlight the main substances that are needed for full development.
Biochemistry
Biochemistry is a science that studies the composition of living organisms, analyzes their structure, transformation, distribution, and functions. Its formation began at the end of the 19th century, when the main classes of substances included in living beings were identified.
Quantitative composition
The chemical composition of the cells of living organisms includes many elements of the periodic table. Depending on the quantitative content, it is customary to distinguish three groups. Often they are called organogenic, since without them the full existence of a living organism is impossible. These elements are able to form covalent bonds, which are the basis of the living world.
Macronutrients
Among the macronutrients, potassium, phosphorus, magnesium, calcium, chlorine, sulfur, and sodium are distinguished. The chemical elements that make up living organisms are needed to ensure metabolic processes.
trace elements
Cobalt, molybdenum, zinc, iodine, vanadium, bromine are part of hormones and enzymes. Their percentage does not exceed 10 percent.
Ultramicroelements
Gold, silver, platinum are also present in living organisms, but their amount is negligible. Chemical elements that are in living organisms are present in them in the form of positive or negative ions. They are important for the nutrition of cells, their full growth, the creation of new tissues, and the maintenance of a normal acid-base balance in the body. What is the chemical composition of living organisms? First of all, according to the chemical composition, one can judge the irritation or excitation of the cell, the level of metabolic processes, and the energy balance.
The chemical composition of living organisms includes mineral salts and water. It is in the aquatic environment that energy is converted, all metabolic reactions occur inside a living organism. The water molecule has the structure of a dipole, in which there exist. It is the shift of electron density from hydrogen atoms to oxygen that is the cause of the appearance of polarization, which determines the exceptional importance of water for the life of the organism. Weak bonds are formed between water molecules, which are almost 20 times less strong than covalent bonds. It is with their help that proteins and nucleic acids are transformed inside the body into other substances, the process is accompanied by the release of energy, which the body needs so much. Water, being a universal solvent, is of particular importance in the life of the organism, because most of all biochemical transformations are carried out in aqueous solutions.
What is the chemical composition of living organisms? In addition to inorganic elements, it contains many other substances. For example, there are proteins and nucleic acids. It is these organic substances that are necessary to protect the body. Which do not dissolve in water include proteins, almost all fats. Analyzing the basic chemical composition of living organisms, we note that it is water that is associated with the regulation of the thermal regime in the body. The body's ability to absorb heat in the event of sudden temperature fluctuations directly depends on it. This property allows the body to protect itself from excessive overheating, to prevent overheating of the body when the temperature in the atmosphere rises. It is thanks to water that a uniform distribution of energy between various tissues occurs, a full-fledged circulation of heat is carried out throughout all organs.
Organic composition
Among the organic compounds present in the human body, carbohydrates and lipids are of particular importance. They are compounds that are formed by high molecular weight fatty acids and trihydric alcohols - glycerol. Lipid molecules are relatively small molecules. They have hydrophobic properties, that is, they do not dissolve in water, but form emulsions. Lipids are highly soluble in non-polar organic solvents such as benzene, chloroform, acetone. What are the main ones? First of all, they are sources of energy. In addition, these organic substances perform a building function in a living organism. Carbohydrates are also of particular importance for the life of the body. In addition to the construction, energy function, they are needed for the supply of nutrients, as well as to protect the body from viruses and bacteria. The regulatory capabilities of carbohydrates lie in the regulatory abilities, implying the protection of the body from mechanical damage. Proteins and proteins are biopolymers with a large relative molecular weight, the monomers of which are organic amino acid residues.
Proteins are hormones, they are necessary to regulate many life processes of organisms. In the body there are also special proteins - enzymes, which are biological catalysts that can slow down or speed up chemical reactions. Knowing the chemical composition of a living organism, one can predict its main functions, properties, and look for ways to apply the knowledge gained.
