At the end of the ninth century AD, the Arab scientist Abu Bakr ar-Razi divided all substances known at that time into 3 groups depending on their origin: mineral, animal and plant. The classification existed for almost 1000 years. Only in the 19th century did 3 groups turn into 2: organic and inorganic substances.

Inorganic substances

Inorganic substances can be simple or complex. Simple substances are those substances that contain atoms of just one chemical element. They are divided into metals and non-metals.

Metals are plastic substances that conduct heat and electricity well. Almost all of them are silvery-white and have a characteristic metallic sheen. Such properties are a consequence of a special structure. In a metal crystal lattice, metal particles (called atom ions) are connected by mobile shared electrons.

Even those who are far from chemistry can name examples of metals. These are iron, copper, zinc, chromium and other simple substances formed by atoms of chemical elements, the symbols of which are located in D.I. Mendeleev under the B – At diagonal and above it in the main subgroups.

Nonmetals, as their name suggests, do not have the properties of metals. They are fragile, and, with rare exceptions, do not conduct electric current and do not shine (except for iodine and graphite). Their properties are more diverse compared to metals.

The reason for such differences also lies in the structure of the substances. In crystal lattices of atomic and molecular types there are no freely moving electrons. Here they combine in pairs to form covalent bonds. Well-known non-metals - oxygen, nitrogen, sulfur, phosphorus and others. Elements - non-metals in PSCE are located above the B-At diagonal

Complex inorganic substances are:

• acids consisting of hydrogen atoms and acid residues (HNO3, H2SO4);
• bases formed by metal atoms and hydroxo groups (NaOH, Ba(OH)2);
• salts whose formulas begin with metal symbols and end with acidic residues (BaSO4, NaNO3);
• oxides formed by two elements, one of them is O in the oxidation state -2 (BaO, Na2O);
• other binary compounds (hydrides, nitrides, peroxides, etc.)

In total, several hundred thousand inorganic substances are known.

Organic matter

Organic compounds differ from inorganic ones primarily in their composition. If inorganic substances can be formed by any elements of the Periodic Table, then organic substances must certainly include C and H atoms. Such compounds are called hydrocarbons (CH4 - methane, C6H6 - benzene). Hydrocarbon raw materials (oil and gas) bring enormous benefits to humanity. However, it also causes serious discord.

Hydrocarbon derivatives also contain O and N atoms. Representatives of oxygen-containing organic compounds are alcohols and their isomeric ethers (C2H5OH and CH3-O-CH3), aldehydes and their isomers - ketones (CH3CH2CHO and CH3COCH3), carboxylic acids and complex ethers (CH3-COOH and HCOOCH3). The latter also include fats and waxes. Carbohydrates are also oxygen-containing compounds.

Why did scientists combine plant and animal substances into one group - organic compounds and how do they differ from inorganic ones? There is no single clear criterion to separate organic and inorganic substances. Let us consider a number of characteristics that unite organic compounds.

1. Composition (built from atoms C, H, O, N, less often P and S).
2. Structure (C-H and C-C bonds are required, they form chains and cycles of different lengths);
3. Properties (all organic compounds are flammable, forming CO2 and H2O during combustion).

Among organic substances there are many polymers of natural (proteins, polysaccharides, natural rubber, etc.), artificial (viscose) and synthetic (plastics, synthetic rubbers, polyester, etc.) origin. They have a large molecular weight and a more complex structure compared to inorganic substances.

Finally, there are more than 25 million organic substances.

This is just a superficial look at organic and inorganic substances. More than a dozen scientific works, articles and textbooks have been written about each of these groups.

Inorganic compounds - video

Chemical composition of the cell

Mineral salts

water.
good solvent

Hydrophilic(from Greek hydro- water and filleo

Hydrophobic(from Greek hydro- water and Phobos

elasticity

Water. Water- universal solvent hydrophilic. 2- hydrophobic. .3- heat capacity. 4- Water is characterized 5- 6- Water provides movement of substances 7- In plants, water determines turgor support functions, 8- Water is an integral part lubricating fluids slime

Mineral salts. action potential ,

Physico-chemical properties of water as the main medium in the human body.

Of the inorganic substances that make up the cell, the most important is water. Its amount ranges from 60 to 95% of the total cell mass. Water plays a vital role in the life of cells and living organisms in general. In addition to the fact that it is part of their composition, for many organisms it is also a habitat. The role of water in a cell is determined by its unique chemical and physical properties, associated mainly with the small size of its molecules, the polarity of its molecules and their ability to form hydrogen bonds with each other.

Lipids. Functions of lipids in the human body.

Lipids are a large group of substances of biological origin, highly soluble in organic solvents such as methanol, acetone, chloroform and benzene. At the same time, these substances are insoluble or slightly soluble in water. Poor solubility is associated with the insufficient content of atoms with a polarizable electron shell, such as O, N, S or P, in lipid molecules.

The system of humoral regulation of physiological functions. Principles of hum..

Humoral physiological regulation uses body fluids (blood, lymph, cerebrospinal fluid, etc.) to transmit information. Signals are transmitted through chemicals: hormones, mediators, biologically active substances (BAS), electrolytes, etc.

Features of humoral regulation: does not have an exact addressee - with the flow of biological fluids, substances can be delivered to any cells of the body; the speed of information delivery is low - determined by the speed of flow of biological fluids - 0.5-5 m/s; duration of action.

The transmission of humoral regulation is carried out by the blood flow, lymph, by diffusion, nervous regulation is carried out by nerve fibers. The humoral signal travels more slowly (with the blood flow through the capillary at a speed of 0.05 mm/s) than the nervous signal (nerve transmission speed is 130 m/s). A humoral signal does not have such a precise addressee (it works on the principle of “everyone, everyone, everyone”) as a nervous one (for example, a nerve impulse is transmitted by the contracting muscles of a finger). But this difference is not significant, since cells have different sensitivity to chemicals. Therefore, chemicals act on strictly defined cells, that is, on those that are able to perceive this information. Cells that have such a high sensitivity to any humoral factor are called target cells.
Among humoral factors, substances with a narrow
spectrum of action, that is, directed action on a limited number of target cells (for example, oxytocin), and wider (for example, adrenaline), for which there is a significant number of target cells.
Humoral regulation is used to ensure reactions that do not require high speed and accuracy of execution.
Humoral regulation, like nervous regulation, is always carried out
a closed regulatory loop in which all elements are interconnected by channels.
As for the monitoring element of the device circuit (SP), it is absent as an independent structure in the humoral regulation circuit. The function of this link is usually performed by the endocrine system.
cell.
Humoral substances that enter the blood or lymph diffuse into the intercellular fluid and are quickly destroyed. In this regard, their effect can only extend to nearby organ cells, that is, their influence is local in nature. In contrast to local effects, distant effects of humoral substances extend to target cells at a distance.

HYPOTHALAMUS HORMONES

hormone effect

Corticoliberin - Stimulates the formation of corticotropin and lipotropin

Gonadotropin-releasing hormone - Stimulates the formation of lutropin and follitropin

Prolactoliberin - Promotes the release of prolactin

Prolactostatin - Inhibits the release of prolactin

Somatoliberin Stimulates the secretion of growth hormone

Somatostatin - Inhibits the secretion of growth hormone and thyrotropin

Thyroliberin - Stimulates the secretion of thyrotropin and prolactin

Melanoliberin - Stimulates the secretion of melanocyte-stimulating hormone

Melanostatin - Inhibits the secretion of melanocyte-stimulating hormone

ADENOGYPOPHYSIC HORMONES

STH (somatotropin, growth hormone) - Stimulates body growth, protein synthesis in cells, glucose formation and lipid breakdown

Prolactin - Regulates lactation in mammals, the instinct to nurse offspring, differentiation of various tissues

TSH (thyrotropin) - Regulates the biosynthesis and secretion of thyroid hormones

Corticotropin - Regulates the secretion of hormones from the adrenal cortex

FSH (follitropin) and LH (luteinizing hormone) - LH regulates the synthesis of female and male sex hormones, stimulates the growth and maturation of follicles, ovulation, the formation and functioning of the corpus luteum in the ovaries FSH has a sensitizing effect on follicles and Leydig cells to the action of LH, stimulates spermatogenesis

THYROID HORMONES The release of thyroid hormones is controlled by two “superior” endocrine glands. The area of ​​the brain that connects the nervous and endocrine systems is called the hypothalamus. The hypothalamus receives information about the level of thyroid hormones and secretes substances that affect the pituitary gland. Pituitary also located in the brain in the area of ​​a special depression - the sella turcica. It secretes several dozen hormones that are complex in structure and action, but only one of them acts on the thyroid gland - thyroid-stimulating hormone or TSH. The level of thyroid hormones in the blood and signals from the hypothalamus stimulate or inhibit the release of TSH. For example, if the amount of thyroxine in the blood is small, then both the pituitary gland and hypothalamus will know about it. The pituitary gland will immediately release TSH, which activates the release of hormones from the thyroid gland.

Humoral regulation is the coordination of the physiological functions of the human body through blood, lymph, and tissue fluid. Humoral regulation is carried out by biologically active substances - hormones that regulate body functions at the subcellular, cellular, tissue, organ and system levels and mediators that transmit nerve impulses. Hormones are produced by the endocrine glands (endocrine), as well as by the external secretion glands (tissue - the walls of the stomach, intestines, and others). Hormones affect the metabolism and activity of various organs, entering them through the blood. Hormones have the following properties: High biological activity; Specificity – effects on certain organs, tissues, cells; They are quickly destroyed in tissues; The molecules are small in size and penetrate easily through the walls of capillaries into tissues.

Adrenal glands - paired endocrine glands of vertebrates animals and person. The zona glomerulosa produces hormones called mineralcorticoids. These include :Aldosterone (basic mineralocorticosteroid hormone adrenal cortex) Corticosterone (insignificant and relatively inactive glucocorticoid hormone). Mineralcorticoids increase reabsorption Na + and K + excretion in the kidneys. In the beam zone there are formed glucocorticoids, which include: Cortisol. Glucocorticoids have an important effect on almost all metabolic processes. They stimulate education glucose from fat And amino acids(gluconeogenesis), oppress inflammatory, immune And allergic reactions, reduce proliferation connective tissue and also increase sensitivity sense organs And nervous system excitability. Produced in the mesh zone sex hormones (androgens, which are precursor substances estrogen). These sex hormones play a slightly different role than the hormones secreted gonads. Adrenal medulla cells produce catecholamines - adrenalin And norepinephrine . These hormones increase blood pressure, increase heart function, dilate the bronchial tubes, and increase blood sugar levels. When at rest, they constantly release small amounts of catecholamines. Under the influence of a stressful situation, the secretion of adrenaline and norepinephrine by the cells of the adrenal medulla increases sharply.

The resting membrane potential is a deficiency of positive electrical charges inside the cell, resulting from the leakage of positive potassium ions from it and the electrogenic action of the sodium-potassium pump.

Action potential (AP). All stimuli acting on the cell primarily cause a decrease in PP; when it reaches a critical value (threshold), an active propagating response—PD—occurs. AP amplitude approximately = 110-120 mv. A characteristic feature of AP, which distinguishes it from other forms of cell response to stimulation, is that it obeys the “all or nothing” rule, i.e., it occurs only when the stimulus reaches a certain threshold value, and a further increase in the intensity of the stimulus no longer affects amplitude, nor on AP duration. The action potential is one of the most important components of the excitation process. In nerve fibers it ensures the conduction of excitation from sensory endings ( receptors) to the body of the nerve cell and from it to the synaptic endings located on various nerve, muscle or glandular cells. The conduction of PD along nerve and muscle fibers is carried out by the so-called. local currents, or currents of action that arise between the excited (depolarized) and the resting sections of the membrane adjacent to it.

Postsynaptic potentials (PSPs) arise in areas of the membrane of nerve or muscle cells directly adjacent to synaptic terminals. They have an amplitude of the order of several mv and duration 10-15 msec. PSPs are divided into excitatory (EPSP) and inhibitory (IPSP).

Generator potentials arise in the membrane of sensitive nerve endings - receptors. Their amplitude is on the order of several mv and depends on the strength of stimulation applied to the receptor. The ionic mechanism of generator potentials has not yet been sufficiently studied.

Action potential

An action potential is a rapid change in membrane potential that occurs when nerve, muscle, and some glandular cells are excited. Its occurrence is based on changes in the ionic permeability of the membrane. In the development of an action potential, four successive periods are distinguished: local response, depolarization, repolarization and trace potentials.

Irritability is the ability of a living organism to respond to external influences by changing its physicochemical and physiological properties. Irritability manifests itself in changes in the current values ​​of physiological parameters that exceed their shifts at rest. Irritability is a universal manifestation of the vital activity of all biosystems. These environmental changes that cause an organism's response can include a wide repertoire of reactions, ranging from diffuse protoplasmic reactions in protozoa to complex, highly specialized reactions in humans. In the human body, irritability is often associated with the property of nervous, muscle and glandular tissues to respond in the form of producing a nerve impulse, muscle contraction or secretion of substances (saliva, hormones, etc.). In living organisms that lack a nervous system, irritability can manifest itself in movements. Thus, amoebas and other protozoa leave unfavorable solutions with high salt concentrations. And plants change the position of the shoots to maximize light absorption (stretch towards the light). Irritability is a fundamental property of living systems: its presence is a classic criterion by which living things are distinguished from nonliving things. The minimum magnitude of the stimulus sufficient for the manifestation of irritability is called the perception threshold. The phenomena of irritability in plants and animals have much in common, although their manifestations in plants differ sharply from the usual forms of motor and nervous activity of animals

Laws of irritation of excitable tissues: 1) law of force– excitability is inversely proportional to the threshold force: the greater the threshold force, the less excitability. However, for excitation to occur, the force of stimulation alone is not enough. It is necessary that this irritation last for some time; 2) law of time action of the stimulus. When the same force is applied to different tissues, different durations of irritation will be required, which depends on the ability of a given tissue to manifest its specific activity, that is, excitability: the least time will be required for tissue with high excitability and the longest time for tissue with low excitability. Thus, excitability is inversely proportional to the duration of the stimulus: the shorter the duration of the stimulus, the greater the excitability. The excitability of tissue is determined not only by the strength and duration of irritation, but also by the rate (speed) of increase in the strength of irritation, which is determined by the third law - law of the rate of increase in the strength of irritation(the ratio of the strength of the stimulus to the time of its action): the greater the rate of increase in the strength of stimulation, the less excitability. Each tissue has its own threshold rate of increase in the strength of irritation.

The ability of a tissue to change its specific activity in response to irritation (excitability) is inversely dependent on the magnitude of the threshold force, the duration of the stimulus and the speed (speed) of increase in the strength of irritation.

The critical level of depolarization is the value of the membrane potential, upon reaching which an action potential occurs. The critical level of depolarization (CLD) is the level of electrical potential of the membrane of an excitable cell from which the local potential turns into an action potential.

A local response occurs to subthreshold stimuli; spreads over 1-2 mm with attenuation; increases with increasing stimulus strength, i.e. obeys the law of “force”; sums up - increases with repeated frequent subthreshold stimulation 10 - 40 mV increases.

The chemical mechanism of synaptic transmission, compared to the electrical one, more effectively provides the basic functions of the synapse: 1) one-way signal transmission; 2) signal amplification; 3) convergence of many signals on one postsynaptic cell, plasticity of signal transmission.

Chemical synapses transmit two types of signals - excitatory and inhibitory. In excitatory synapses, the neurotransmitter released from the presynaptic nerve endings causes an excitatory post-synaptic potential in the postsynaptic membrane - local depolarization, and in inhibitory synapses - an inhibitory postsynaptic potential, as a rule, hyperpolarization. The decrease in membrane resistance that occurs during an inhibitory postsynaptic potential short-circuits the excitatory postsynaptic current, thereby weakening or blocking the transmission of excitation.

Chemical composition of the cell

Organisms are made up of cells. Cells of different organisms have similar chemical compositions. About 90 elements are found in the cells of living organisms, and about 25 of them are found in almost all cells. Based on their content in the cell, chemical elements are divided into three large groups: macroelements (99%), microelements (1%), ultramicroelements (less than 0.001%).

Macroelements include oxygen, carbon, hydrogen, phosphorus, potassium, sulfur, chlorine, calcium, magnesium, sodium, iron. Microelements include manganese, copper, zinc, iodine, fluorine. Ultramicroelements include silver, gold, bromine, selenium.

A deficiency of any element can lead to illness and even death of the body, since each element plays a specific role. Macroelements of the first group form the basis of biopolymers - proteins, carbohydrates, nucleic acids, as well as lipids, without which life is impossible. Sulfur is part of some proteins, phosphorus is part of nucleic acids, iron is part of hemoglobin, and magnesium is part of chlorophyll. Calcium plays an important role in metabolism. Some of the chemical elements contained in the cell are part of inorganic substances - mineral salts and water.

Mineral salts are found in the cell, as a rule, in the form of cations (K +, Na +, Ca 2+, Mg 2+) and anions (HPO 2-/4, H 2 PO -/4, CI -, HCO 3), the ratio of which determines the acidity of the environment, which is important for the life of cells.

Of the inorganic substances in living nature, plays a huge role water.
It makes up a significant mass of most cells. A lot of water is contained in the cells of the brain and human embryos: more than 80% water; in adipose tissue cells - only 40.% By old age, the water content in cells decreases. A person who has lost 20% of water dies. The unique properties of water determine its role in the body. It is involved in thermoregulation, which is due to the high heat capacity of water - the consumption of a large amount of energy when heating. Water - good solvent. Due to their polarity, its molecules interact with positively and negatively charged ions, thereby promoting the dissolution of the substance. In relation to water, all cell substances are divided into hydrophilic and hydrophobic.

Hydrophilic(from Greek hydro- water and filleo- love) are called substances that dissolve in water. These include ionic compounds (for example, salts) and some non-ionic compounds (for example, sugars).

Hydrophobic(from Greek hydro- water and Phobos- fear) are substances that are insoluble in water. These include, for example, lipids.

Water plays an important role in the chemical reactions that occur in the cell in aqueous solutions. It dissolves metabolic products that the body does not need and thereby promotes their removal from the body. The high water content in the cell gives it elasticity. Water facilitates the movement of various substances within a cell or from cell to cell.

Inorganic compounds in the human body.

Water. Of the inorganic substances that make up the cell, the most important is water. Its amount ranges from 60 to 95% of the total cell mass. Water plays a vital role in the life of cells and living organisms in general. In addition to the fact that it is part of their composition, for many organisms it is also a habitat. The role of water in a cell is determined by its unique chemical and physical properties, associated mainly with the small size of its molecules, the polarity of its molecules and their ability to form hydrogen bonds with each other. Water as a component of biological systems performs the following essential functions: 1- Water- universal solvent for polar substances, such as salts, sugars, alcohols, acids, etc. Substances that are highly soluble in water are called hydrophilic. 2- Water does not dissolve non-polar substances and does not mix with them, since it cannot form hydrogen bonds with them. Substances that are insoluble in water are called hydrophobic. Hydrophobic molecules or parts of them are repelled by water, and in its presence they are attracted to each other. Such interactions play an important role in ensuring the stability of membranes, as well as many protein molecules, nucleic acids, and a number of subcellular structures. .3- Water has a high specific heat capacity. 4- Water is characterized high heat of vaporization, i.e. e. the ability of molecules to carry away a significant amount of heat while simultaneously cooling the body. 5- It is exclusively characteristic of water high surface tension. 6- Water provides movement of substances in the cell and body, absorption of substances and excretion of metabolic products. 7- In plants, water determines turgor cells, and in some animals performs support functions, being a hydrostatic skeleton (round and annelids, echinoderms). 8- Water is an integral part lubricating fluids(synovial - in the joints of vertebrates, pleural - in the pleural cavity, pericardial - in the pericardial sac) and slime(facilitate the movement of substances through the intestines, create a moist environment on the mucous membranes of the respiratory tract). It is part of saliva, bile, tears, sperm, etc.

Mineral salts. Modern methods of chemical analysis have revealed 80 elements of the periodic table in the composition of living organisms. Based on their quantitative composition, they are divided into three main groups. Macroelements make up the bulk of organic and inorganic compounds, their concentration ranges from 60% to 0.001% of body weight (oxygen, hydrogen, carbon, nitrogen, sulfur, magnesium, potassium, sodium, iron, etc.). Microelements are mainly ions of heavy metals. Contained in organisms in the amount of 0.001% - 0.000001% (manganese, boron, copper, molybdenum, zinc, iodine, bromine). The concentration of ultramicroelements does not exceed 0.000001%. Their physiological role in organisms has not yet been fully elucidated. This group includes uranium, radium, gold, mercury, cesium, selenium and many other rare elements. Not only the content, but also the ratio of ions in the cell is significant. The difference between the amounts of cations and anions on the surface and inside the cell ensures the occurrence action potential , which underlies the occurrence of nervous and muscle excitation.

The bulk of the tissues of living organisms inhabiting the Earth are made up of organogenic elements: oxygen, carbon, hydrogen and nitrogen, from which organic compounds are mainly built - proteins, fats, carbohydrates.

To the question of substance. what are organic substances and inorganic... the human body consists of what substances? given by the author LEV RYKOV the best answer is Organic substances, organic compounds - a class of compounds that contain carbon (with the exception of carbides, carbonic acid, carbonates, carbon oxides and cyanides). Organic compounds are usually made up of chains of carbon atoms linked together by covalent bonds and various substituents attached to these carbon atoms
An inorganic substance or inorganic compound is a chemical substance, a chemical compound that is not organic, that is, it does not contain carbon (except for carbides, cyanides, carbonates, carbon oxides and some other compounds that are traditionally classified as inorganic). Inorganic compounds do not have the carbon skeleton characteristic of organic ones.
The human body contains both substances. I already wrote in previous answers to your questions that the main inorganic substances contained in the human body are water and calcium salts (the latter mainly makes up the human skeleton).
Organic compounds are mainly proteins, fats and carbohydrates, in addition, there are complex compounds that act as an intermediate link (for example, hemoglobin - a complex of iron with organic ligands)

Answer from Kirsimarja[guru]
organic substances are compounds of carbon with other elements
inorganic, to put it simply, is what is contained in the periodic table.
The human body contains absolutely all substances, both organic and inorganic

Answer from Helen[guru]
The human body consists of 60% water, 34% organic matter and 6% inorganic matter. The main components of organic substances are carbon, hydrogen, oxygen, they also include nitrogen, phosphorus and sulfur. In the inorganic substances of the human body, 22 chemical elements are necessarily present: Ca, P, O, Na, Mg, S, B, C1, K, V, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cr, Si, I ,F,Se. For example, if a person weighs 70 kg, then it contains (in grams): calcium - 1700, potassium - 250, sodium - 70, magnesium - 42, iron - 5, zinc - 3. Living organisms contain various chemicals elements. Conventionally, depending on the concentration of chemical elements in the body, macro- and microelements are distinguished.
Macroelements are considered to be those chemical elements whose content in the body is more than 0.005% of body weight. Macroelements include hydrogen, carbon, oxygen, nitrogen, sodium, magnesium, phosphorus, sulfur, chlorine, potassium, and calcium.
Microelements are chemical elements found in the body in very small quantities. Their content does not exceed 0.005% of body weight, and their concentration in tissues does not exceed 0.000001%. Among all microelements, the so-called essential microelements are classified into a special group.
Essential microelements are microelements, the regular intake of which with food or water into the body is absolutely necessary for its normal functioning. Essential microelements are part of enzymes, vitamins, hormones and other biologically active substances. Essential microelements are iron, iodine, copper, manganese, zinc, cobalt, molybdenum, selenium, chromium, fluorine.
The role of macroelements that make up inorganic substances is obvious. For example, the main amount of calcium and phosphorus enters the bones (calcium hydroxyphosphate Ca10(PO4)6(OH) 2), and chlorine in the form of hydrochloric acid is contained in gastric juice.
Microelements are included in the above-mentioned series of 22 elements that are necessarily present in the human body. Note that most of them are metals, and of the metals, more than half are d-elements. The latter form coordination compounds in the body with complex organic molecules.
Characteristic symptoms of deficiency of chemical elements in the human body
Ca Growth slowdown
Mg Muscle cramps
Fe Anemia, immune system disorder
Zn Skin damage, growth retardation, sexual maturation delay
Cu Arterial weakness, liver dysfunction, secondary anemia
Mn Infertility, impaired skeletal growth
Mo Slow cell growth, caries susceptibility
Co Pernicious anemia
Ni Increased incidence of depression, dermatitis
Cr Diabetes symptoms
Si Skeletal growth disorder
F Dental caries
I Thyroid gland dysfunction, slow metabolism
Se Muscular (particularly cardiac) weakness

Answer from Bogdan Bondarenko[newbie]
name any substances

Answer from Egor Shazam[newbie]

Introduction

I chose a rather complex topic, since it combines many sciences, the study of which is very important in the world: biology, ecology, chemistry, etc. My topic is significant in school chemistry and biology courses. Man is a very complex living organism, but studying him seemed quite interesting to me. I believe that every person should know what they consist of.

Target: study in more detail the chemical elements that make up humans and their interaction in the body.

To achieve this goal, the following were set: tasks:

• 1) Study the elemental composition of living organisms;
• 2) Identify the main groups of chemical elements: micro- and macroelements;
• 3) Determine which chemical elements are responsible for growth, muscle function, nervous system, etc.;
• 4) Conduct laboratory experiments confirming the presence of carbon, nitrogen and iron in the human body.

Methods and techniques: analysis of scientific literature, comparative analysis, synthesis, classification and generalization of selected material; observation method, experiment (physical and chemical).

Chemical elements in the human body

All living organisms on Earth, including humans, are in close contact with the environment. Food and drinking water contribute to the entry of almost all chemical elements into the body. They are introduced into and removed from the body every day. Analyzes have shown that the number of individual chemical elements and their ratio in the healthy body of different people is approximately the same.

Many scientists believe that not only are all chemical elements present in a living organism, but each of them performs a specific biological function. The role of about 30 chemical elements has been reliably established, without which the human body cannot exist normally. These elements are called vital. The human body consists of 60% water, 34% organic and 6% inorganic substances.

The body of a person weighing 70 kg consists of:

Carbon - 12.6 kg Chlorine - 200 grams

Oxygen-45.5 kg Phosphorus-0.7 kg

Hydrogen-7 kg Sulfur-175 grams

Nitrogen-2.1 kg Iron-5 grams

Calcium-1.4 kg Fluorine-100 grams

Sodium-150 grams Silicon-3 grams

Potassium-100 grams Iodine-0.1 grams

Magnesium-200 grams Arsenic-0.0005 grams

4 pillars of life

Carbon, oxygen, nitrogen and hydrogen are the four chemical elements that chemists call the “whales of chemistry”, and which at the same time are the basic elements of life. Not only living proteins, but all of nature around us and in us are built from the molecules of these four elements.

In isolation, carbon is a dead stone. Nitrogen, like oxygen, is a free gas. Nitrogen is not bound by anything. Hydrogen combined with oxygen forms water, and together they create the Universe.

In their simple compounds they are water on Earth, clouds in the atmosphere and air. In more complex compounds, these are carbohydrates, salts, acids, alkalis, alcohols, sugars, fats and proteins. Becoming even more complex, they reach the highest stage of development - they create life.

Carbon - the basis of life.

All organic substances from which living organisms are built differ from inorganic ones in that they are based on the chemical element carbon. Organic substances also contain other elements: hydrogen, oxygen, nitrogen, sulfur and phosphorus. But they all cluster around carbon, which is the main central element.

Academician Fersman called it the basis of life, because without carbon life is impossible. There is no other chemical element with such unique properties as carbon.

However, this does not mean that carbon makes up the bulk of living matter. In any organism there is only 10% carbon, 80% water, and the remaining ten percent comes from other chemical elements that make up the body.

A characteristic feature of carbon in organic compounds is its unlimited ability to bind different elements into atomic groups in a variety of combinations.

Inorganic substances are chemical compounds that, unlike organic ones, do not contain carbon (except for cyanides, carbides, carbonates and some other compounds traditionally belonging to this group).

The classification of inorganic substances is as follows. There are simple substances: nonmetals (H2, N2, O2), metals (Na, Zn, Fe), amphoteric simple substances (Mn, Zn, Al), noble gases (Xe, He, Rn) and complex substances: oxides (H2O, CO2, P2O5); hydroxides (Ca(OH)2, H2SO4); salts (CuSO4, NaCl, KNO3, Ca3(PO4)2) and binary compounds.

Molecules of simple (single-element) substances consist only of atoms of a certain (one) type (element). They do not decompose in chemical reactions and are not capable of forming other substances. Simple substances, in turn, are divided into metals and non-metals. There is no clear boundary between them due to the ability of simple substances to exhibit dual properties. Some elements simultaneously exhibit properties of both metals and non-metals. They are called amphoteric.

Noble gases are a separate class of inorganic substances; they stand out among others by their special originality. VIIIA-groups.

The ability of some elements to form several simple ones, differing in structure and properties, is called allotropy. Examples include the elements C, diamond-forming carbine and graphite; O - ozone and oxygen; R - white, red, black and others. This phenomenon is possible due to the different number of atoms in the molecule and due to the ability of atoms to form different crystalline forms.

In addition to simple ones, the main classes of inorganic substances include complex compounds. Complex (two- or multi-element) substances mean compounds of chemical elements. Their molecules are made up of different types of atoms (different elements). When decomposed in chemical reactions, they form several other substances. They are divided into bases and salts.

In bases, metal atoms are connected to hydroxyl groups (or one group). These compounds are divided into soluble (alkali) and insoluble in water.

Oxides consist of two elements, one of which is necessarily oxygen. They are non-salt-forming and salt-forming.

Hydroxides are substances that are formed by interaction (direct or indirect) with water. These include: bases (Al(OH)3, Ca(OH)2), acids (HCl, H2SO4, HNO3, H3PO4), (Al(OH)3, Zn(OH)2). When different types of hydroxides interact with each other, oxygen-containing salts are formed.

Salts are divided into medium salts (consist of cations and anions - Ca3(PO4)2, Na2SO4); acidic (contain hydrogen atoms in the acidic residue, which can be replaced by cations -NaHSO3, CaHPO4), basic (contain a hydroxo or oxo group - Cu2CO3(OH)2); double (contain two different chemical cations) and/or complex (contain two different acidic residues) salts (CaMg(CO3)2, K3).

Binary compounds (a fairly large class of substances) are divided into oxygen-free acids (H2S, HCl); oxygen-free salts (CaF2, NaCl) and other compounds (CaC2, AlH3, CS2).

Inorganic substances do not have a carbon skeleton, which is the basis of organic compounds.

The human body contains both (34%) and inorganic compounds. The latter include, first of all, water (60%) and calcium salts, of which the human skeleton mainly consists.

Inorganic substances in the human body are represented by 22 chemical elements. Most of them are metals. Depending on the concentration of elements in the body, they are called micro-elements (the content of which in the body is not more than 0.005% of body weight) and macroelements. Microelements essential for the body are iodine, iron, copper, zinc, manganese, molybdenum, cobalt, chromium, selenium, and fluorine. Their intake from food into the body is necessary for its normal functioning. Macroelements such as calcium, phosphorus and chlorine are the basis of many tissues.