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organic matter. Classes of organic substances

There are several definitions of what organic substances are, how they differ from another group of compounds - inorganic. One of the most common explanations comes from the name "hydrocarbons". Indeed, at the heart of all organic molecules are chains of carbon atoms bonded to hydrogen. There are other elements that have received the name "organogenic".

Organic chemistry before the discovery of urea

Since ancient times, people have used many natural substances and minerals: sulfur, gold, iron and copper ore, table salt. Throughout the existence of science - from ancient times to the first half of the 19th century - scientists could not prove the connection between animate and inanimate nature at the level of microscopic structure (atoms, molecules). It was believed that organic substances owe their appearance to the mythical life force - vitalism. There was a myth about the possibility of growing a little man "homunculus". To do this, it was necessary to put various waste products into a barrel, wait a certain time until the vital force was born.

A crushing blow to vitalism was dealt by the work of Weller, who synthesized the organic substance urea from inorganic components. So it was proved that there is no life force, nature is one, organisms and inorganic compounds are formed by atoms of the same elements. The composition of urea was known even before Weller's work; the study of this compound was not difficult in those years. Remarkable was the very fact of obtaining a substance characteristic of metabolism outside the body of an animal or a person.

Theory of A. M. Butlerov

The role of the Russian school of chemists in the development of the science that studies organic substances is great. Whole epochs in the development of organic synthesis are associated with the names of Butlerov, Markovnikov, Zelinsky, Lebedev. The founder of the theory of the structure of compounds is A. M. Butlerov. The famous chemist in the 60s of the XIX century explained the composition of organic substances, the reasons for the diversity of their structure, revealed the relationship that exists between the composition, structure and properties of substances.

On the basis of Butlerov's conclusions, it was possible not only to systematize knowledge about already existing organic compounds. It became possible to predict the properties of substances not yet known to science, to create technological schemes for their production in industrial conditions. Many of the ideas of leading organic chemists are being fully implemented today.

When hydrocarbons are oxidized, new organic substances are obtained - representatives of other classes (aldehydes, ketones, alcohols, carboxylic acids). For example, large volumes of acetylene are used to produce acetic acid. Part of this reaction product is further consumed to obtain synthetic fibers. An acid solution (9% and 6%) is in every home - this is ordinary vinegar. Oxidation of organic substances serves as the basis for obtaining a very large number of compounds of industrial, agricultural, and medical importance.

aromatic hydrocarbons

Aromaticity in organic molecules is the presence of one or more benzene nuclei. A chain of 6 carbon atoms closes into a ring, a conjugated bond appears in it, so the properties of such hydrocarbons are not similar to other hydrocarbons.

Aromatic hydrocarbons (or arenes) are of great practical importance. Many of them are widely used: benzene, toluene, xylene. They are used as solvents and raw materials for the production of drugs, dyes, rubber, rubber and other products of organic synthesis.

Oxygen compounds

Oxygen atoms are present in a large group of organic substances. They are part of the most active part of the molecule, its functional group. Alcohols contain one or more hydroxyl species —OH. Examples of alcohols: methanol, ethanol, glycerin. In carboxylic acids, there is another functional particle - carboxyl (-COOOH).

Other oxygen-containing organic compounds are aldehydes and ketones. Carboxylic acids, alcohols and aldehydes are present in large quantities in various plant organs. They can be sources for obtaining natural products (acetic acid, ethyl alcohol, menthol).

Fats are compounds of carboxylic acids and the trihydric alcohol glycerol. In addition to linear alcohols and acids, there are organic compounds with a benzene ring and a functional group. Examples of aromatic alcohols: phenol, toluene.

Carbohydrates

The most important organic substances of the body that make up the cells are proteins, enzymes, nucleic acids, carbohydrates and fats (lipids). Simple carbohydrates - monosaccharides - are found in cells in the form of ribose, deoxyribose, fructose and glucose. The last carbohydrate in this short list is the main substance of metabolism in cells. Ribose and deoxyribose are constituents of ribonucleic and deoxyribonucleic acids (RNA and DNA).

When glucose molecules are broken down, the energy necessary for life is released. First, it is stored in the formation of a kind of energy transfer - adenosine triphosphoric acid (ATP). This substance is carried by the blood, delivered to tissues and cells. With the successive cleavage of three phosphoric acid residues from adenosine, energy is released.

Fats

Lipids are substances of living organisms that have specific properties. They do not dissolve in water, are hydrophobic particles. The seeds and fruits of some plants, nervous tissue, liver, kidneys, blood of animals and humans are especially rich in substances of this class.

Human and animal skin contains many small sebaceous glands. The secret secreted by them is displayed on the surface of the body, lubricates it, protects it from moisture loss and the penetration of microbes. The layer of subcutaneous fatty tissue protects internal organs from damage, serves as a reserve substance.

Squirrels

Proteins make up more than half of all organic substances of the cell, in some tissues their content reaches 80%. All types of proteins are characterized by high molecular weights, the presence of primary, secondary, tertiary and quaternary structures. When heated, they are destroyed - denaturation occurs. The primary structure is a huge chain of amino acids for the microcosm. Under the action of special enzymes in the digestive system of animals and humans, the protein macromolecule breaks down into its constituent parts. They enter the cells, where the synthesis of organic substances takes place - other proteins specific to each living being.

Enzymes and their role

Reactions in the cell proceed at a rate that is difficult to achieve under industrial conditions, thanks to catalysts - enzymes. There are enzymes that act only on proteins - lipases. The hydrolysis of starch occurs with the participation of amylase. Lipases are needed to decompose fats into their constituent parts. Processes involving enzymes occur in all living organisms. If a person does not have any enzyme in the cells, then this affects the metabolism, in general, health.

Nucleic acids

Substances, first discovered and isolated from cell nuclei, perform the function of transmitting hereditary traits. The main amount of DNA is contained in chromosomes, and RNA molecules are located in the cytoplasm. With the reduplication (doubling) of DNA, it becomes possible to transfer hereditary information to germ cells - gametes. When they merge, the new organism receives genetic material from the parents.