What refers to the molecular level of life organization. Basic levels of life organization
The world of wildlife is a collection of biological systems of different levels of organization and different subordination. They are in constant interaction. There are several levels of living matter:
Molecular- any living system, no matter how complex it is organized, manifests itself at the level of functioning of biological macromolecules: nucleic acids, proteins, polysaccharides, as well as important organic substances. From this level, the most important processes of the organism's vital activity begin: metabolism and energy conversion, transmission of hereditary information, etc. - the most ancient level of the structure of living nature, bordering on inanimate nature.
Cellular- a cell is a structural and functional unit, also a unit of reproduction and development of all living organisms living on Earth. There are no non-cellular life forms, and the existence of viruses only confirms this rule, since they can exhibit the properties of living systems only in cells.
Tissue- Tissue is a collection of cells similar in structure, united by the performance of a common function.
Organ- in most animals, an organ is a structural and functional combination of several types of tissues. For example, human skin as an organ includes epithelium and connective tissue, which together perform a number of functions, among which the most significant is protective.
Organismic- a multicellular organism is an integral system of organs specialized to perform various functions. Differences between plants and animals in the structure and methods of nutrition. The relationship of organisms with the environment, their adaptability to it.
population-species- a set of organisms of the same species, united by a common habitat, creates a population as a system of a supra-organismal order. In this system, the simplest, elementary evolutionary transformations are carried out.
Biogeocenotic- biogeocenosis - a set of organisms of different species and varying complexity of organization, all environmental factors.
biospheric The biosphere is the highest level of organization of living matter on our planet, including all life on Earth. Thus, living nature is a complexly organized hierarchical system.
2. Reproduction at the cellular level, mitosis and its biological role
Mitosis (from Greek mitos - thread), a type of cell division, as a result of which daughter cells receive genetic material identical to that contained in the mother cell. Karyokinesis, indirect cell division, is the most common method of cell reproduction (reproduction), which ensures the identical distribution of genetic material between daughter cells and the continuity of chromosomes in a number of cell generations.
Rice. 1. Scheme of mitosis: 1, 2 - prophase; 3 - prometaphase; 4 - metaphase; 5 - anaphase; 6 - early telophase; 7 - late telophase
The biological significance of mitosis is determined by the combination of the doubling of chromosomes in it by means of their longitudinal splitting and uniform distribution between daughter cells. The onset of mitosis is preceded by a period of preparation, including the accumulation of energy, the synthesis of deoxyribonucleic acid (DNA), and the reproduction of centrioles. The source of energy is rich in energy, or the so-called macroergic compounds. Mitosis is not accompanied by an increase in respiration, since oxidative processes occur in the interphase (the filling of the “energy reserve of the macaw”). Periodic filling and emptying of the energy reserve of the macaw is the basis of the energy of mitosis.
The stages of mitosis are as follows. Single process. Mitosis is usually divided into 4 stages: prophase, metaphase, anaphase, and telophase.
Rice. Fig. 2. Mitosis in the meristematic cells of the onion root (micrograph). Interphase
Rice. Fig. 3. Mitosis in the meristematic tufts of the onion root (micrograph). Prophase (loose tangle figure)
Rice. 4. Mitosis in the meristematic cells of the onion root (micrograph). Late prophase (destruction of the nuclear membrane)
METAPHASE - consists in the movement of CHROMOSOMES to the equatorial plane (metakinesis, or prometaphase), the formation of the equatorial PLATE ("mother star") and in the separation of chromatids, or sister chromosomes.
Rice. Fig. 5. Mitosis in the meristematic cells of the onion root (micrograph). prometaphase
Fig.6. Mitosis in the meristematic cells of the onion root (micrograph). metaphase
Rice. Fig. 7. Mitosis in the meristematic cells of the onion root (micrograph). Anaphase
Anaphase - the stage of divergence of chromosomes to the poles. Anaphase movement is associated with the elongation of the central filaments of VERETIN, which pushes the mitotic poles apart, and with the shortening of the chromosomal MICROTUBES of the mitotic apparatus. The elongation of the central filaments of the SPINDLE occurs either due to the POLARIZATION of "reserve macromolecules" that complete the construction of the MICROTUBES of the spindle, or due to the dehydration of this structure. The shortening of chromosomal microtubules is provided by the PROPERTIES of the contractile proteins of the mitotic apparatus, which are capable of contraction without thickening. TELOPHASE - consists in the reconstruction of daughter nuclei from chromosomes gathered at the poles, the division of the cell body (CYTOTHYMIA, CYTOKINESIS) and the final destruction of the mitotic apparatus with the FORMATION of an intermediate body. Reconstruction of daughter nuclei is associated with chromosome desperalization, RESTORATION of the nucleolus and nuclear envelope. Cytotomy is carried out by the formation of a cell plate (in a plant cell) or by the formation of a fission furrow (in an animal cell).
Fig.8. Mitosis in the meristematic cells of the onion root (micrograph). Early telophase
Rice. Fig. 9. Mitosis in the meristematic cells of the onion root (micrograph). late telophase
The mechanism of cytotomy is associated either with the contraction of the gelatinized ring of the CYTOPLASMA encircling the EQUATOR (the “contractile ring” hypothesis) or with the expansion of the cell surface due to the straightening of the loop-like protein chains (the “MEMBRANE expansion” hypothesis)
Mitosis duration- depends on the size of the cells, their ploidy, the number of nuclei, as well as on environmental conditions, in particular on temperature. Mitosis lasts 30–60 minutes in animal cells, and 2–3 hours in plant cells. Longer stages of mitosis associated with the processes of synthesis (preprophase, prophase, telophase) self-movement of chromosomes (metakinesis, anaphase) is carried out quickly.
THE BIOLOGICAL SIGNIFICANCE OF MITOSIS - the constancy of the structure and the correct functioning of the organs and tissues of a multicellular organism would be impossible without the preservation of the same set of genetic material in countless cell generations. Mitosis provides important manifestations of vital activity: embryonic development, growth, restoration of organs and tissues after damage, maintenance of the structural integrity of tissues with constant loss of cells in the course of their functioning (replacement of dead erythrocytes, skin cells, intestinal epithelium, etc.) In protozoa, mitosis provides asexual reproduction.
3. Gametogenesis, characterization of germ cells, fertilization
Sex cells (gametes) - male spermatozoa and female eggs (or eggs) develop in the sex glands. In the first case, the path of their development is called SPERMATOGENESIS (from the Greek sperm - seed and genesis - origin), in the second - OVOGENESIS (from Latin ovo - egg)
Gametes are sex cells, their participation in fertilization, the formation of a zygote (the first cell of a new organism). The result of fertilization is the doubling of the number of chromosomes, the restoration of their diploid set in the zygote. Features of gametes are a single, haploid set of chromosomes compared to the diploid set of chromosomes in body cells2. Stages of development of germ cells: 1) increase by mitosis in the number of primary germ cells with a diploid set of chromosomes, 2) growth of primary germ cells, 3) maturation of germ cells.
STAGES OF GAMETOGENESIS - in the process of development of sexual both spermatozoa and eggs, stages are distinguished (fig.). The first stage is the period of reproduction, in which the primary germ cells divide by mitosis, as a result of which their number increases. During spermatogenesis, the reproduction of primary germ cells is very intense. It begins with the onset of puberty and proceeds throughout the entire reproductive period. Reproduction of female primary germ cells in lower vertebrates continues almost all life. In humans, these cells multiply with the greatest intensity only in the prenatal period of development. After the formation of the female sex glands - the ovaries, the primary germ cells stop dividing, most of them die and are absorbed, the rest remain dormant until puberty.
The second stage is the period of growth. In immature male gametes, this period is expressed unsharply. The sizes of male gametes increase slightly. On the contrary, future eggs - oocytes sometimes increase hundreds, thousands and even millions of times. In some animals, oocytes grow very quickly - within a few days or weeks, in others, growth continues for months and years. The growth of oocytes is carried out due to substances formed by other cells of the body.
The third stage is the period of maturation, or meiosis (Fig. 1).
Rice. 9. Scheme of the formation of germ cells
Cells entering the period of meiosis contain a diploid set of chromosomes and already double the amount of DNA (2n 4c).
In the process of sexual reproduction, organisms of any species from generation to generation retain their characteristic number of chromosomes. This is achieved by the fact that before the fusion of germ cells - fertilization - in the process of maturation, the number of chromosomes decreases (reduces) in them, i.e. from a diploid set (2n) a haploid set (n) is formed. The patterns of meiosis in male and female germ cells are essentially the same.
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- Metabolism (as well as at the cellular level).
- Interaction not only between organisms, but also with the environment.
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There are such levels of organization of living matter - levels of biological organization: molecular, cellular, tissue, organ, organism, population-species and ecosystem.
Molecular level of organization- this is the level of functioning of biological macromolecules - biopolymers: nucleic acids, proteins, polysaccharides, lipids, steroids. From this level, the most important life processes begin: metabolism, energy conversion, transmission of hereditary information. This level is studied: biochemistry, molecular genetics, molecular biology, genetics, biophysics.
This is the level of cells (cells of bacteria, cyanobacteria, unicellular animals and algae, unicellular fungi, cells of multicellular organisms). A cell is a structural unit of the living, a functional unit, a unit of development. This level is studied by cytology, cytochemistry, cytogenetics, microbiology.
Tissue level of organization- This is the level at which the structure and functioning of tissues is studied. This level is studied by histology and histochemistry.
Organ level of organization- This is the level of organs of multicellular organisms. Anatomy, physiology, embryology study this level.
Organismal level of organization- this is the level of unicellular, colonial and multicellular organisms. The specificity of the organismic level is that at this level the decoding and implementation of genetic information takes place, the formation of features inherent in individuals of a given species. This level is studied by morphology (anatomy and embryology), physiology, genetics, paleontology.
Population-species level is the level of aggregates of individuals - populations and species. This level is studied by systematics, taxonomy, ecology, biogeography, population genetics. At this level, the genetic and ecological characteristics of populations, elementary evolutionary factors and their impact on the gene pool (microevolution), the problem of species conservation are studied.
Ecosystem level of organization- this is the level of microecosystems, mesoecosystems, macroecosystems. At this level, types of nutrition, types of relationships between organisms and populations in an ecosystem, population size, population dynamics, population density, ecosystem productivity, successions are studied. This level studies ecology.
Allocate also biospheric level of organization living matter. The biosphere is a giant ecosystem that occupies part of the geographic envelope of the Earth. This is a mega ecosystem. In the biosphere, there is a cycle of substances and chemical elements, as well as the conversion of solar energy.
2. Nucleic acids (DNA and RNA) and proteins attract attention as the substrate of life. Nucleic acids are complex chemical compounds containing carbon, oxygen, hydrogen, nitrogen and phosphorus. DNA is the genetic material of cells and determines the chemical specificity of genes. Under the control of DNA, protein synthesis takes place, in which RNA participates. All living organisms in nature consist of the same levels of organization; this is a characteristic biological pattern common to all living organisms. The following levels of organization of living organisms are distinguished: Molecular-genetic level.
This is the most elementary level characteristic of life. No matter how complex or simple the structure of any living organism, they all consist of the same molecular compounds. An example of this is nucleic acids, proteins, carbohydrates and other complex molecular complexes of organic and inorganic substances.
They are sometimes called biological macromolecular substances. At the molecular level, various life processes of living organisms take place: metabolism, energy conversion. With the help of the molecular level, the transfer of hereditary information is carried out, individual organelles are formed and other processes occur.
Cellular level.
The cell is the structural and functional unit of all living organisms on Earth. Individual organelles in the cell have a characteristic structure and perform a specific function. The functions of individual organelles in the cell are interconnected and perform common life processes.
In unicellular organisms (unicellular algae and protozoa), all life processes take place in one cell, and one cell exists as a separate organism. Remember unicellular algae, chlamydomonas, chlorella and protozoa - amoeba, infusoria, etc. In multicellular organisms, one cell cannot exist as a separate organism, but it is an elementary structural unit of the organism.
tissue level.
A set of cells and intercellular substances similar in origin, structure and functions forms a tissue. The tissue level is typical only for multicellular organisms. Also, individual tissues are not an independent holistic organism. For example, the bodies of animals and humans are made up of four different tissues (epithelial, connective, muscle, and nervous). Plant tissues are called: educational, integumentary, supporting, conductive and excretory. Recall the structure and functions of individual tissues.
Organ level.
In multicellular organisms, the union of several identical tissues, similar in structure, origin and functions, forms the organ level. Each organ contains several tissues, but among them one is the most significant. A separate organ cannot exist as a whole organism. Several organs, similar in structure and function, unite to form an organ system, for example, digestion, respiration, blood circulation, etc.
Organism level.
Plants (chlamydomonas, chlorella) and animals (amoeba, infusoria, etc.), whose bodies consist of one cell, are an independent organism. A separate individual of multicellular organisms is considered as a separate organism. In each individual organism, all the vital processes characteristic of all living organisms take place - nutrition, respiration, metabolism, irritability, reproduction, etc. Each independent organism leaves behind offspring.
In multicellular organisms, cells, tissues, organs and organ systems are not a separate organism. Only an integral system of organs specialized in performing various functions forms a separate independent organism. The development of an organism, from fertilization to the end of life, takes a certain period of time. This individual development of each organism is called ontogeny. An organism can exist in close relationship with the environment.
Population-species level.
An aggregate of individuals of one species or a group that exists for a long time in a certain part of the range relatively apart from other aggregates of the same species constitutes a population. At the population level, the simplest evolutionary transformations are carried out, which contributes to the gradual emergence of a new species.
Biogeocenotic level.
The totality of organisms of different species and organization of varying complexity, adapted to the same environmental conditions, is called a biogeocenosis, or natural community. The composition of biogeocenosis includes numerous types of living organisms and environmental conditions. In natural biogeocenoses, energy is accumulated and transferred from one organism to another. Biogeocenosis includes inorganic, organic compounds and living organisms.
biospheric level.
The totality of all living organisms on our planet and their common natural habitat constitutes the biospheric level. At the biospheric level, modern biology solves global problems, such as determining the intensity of the formation of free oxygen by the Earth's vegetation cover or changes in the concentration of carbon dioxide in the atmosphere associated with human activities.
In particular, the properties of living things can be called:
1. Self-renewal, which is associated with a constant exchange of matter and energy, and which is based on the ability to store and use biological information in the form of unique information molecules: proteins and nucleic acids.
2. Self-reproduction, which ensures continuity between generations of biological systems.
3. Self-regulation, which is based on the flow of matter, energy and information.
4. Most of the chemical processes in the body are not in a dynamic state.
5. Living organisms are capable of growth.
permanent, which spend their entire life cycle in the host organism, using it as a source of food and habitat (for example, ascaris, tapeworms, lice);
but) intracavitary - localized in cavities connected to the external environment (for example, in the intestine - ascaris, whipworm);
b) tissue localized in tissues and closed cavities; (eg, liver fluke, tapeworm cysticerci);
in) intracellular- localized in cells; (e.g. malarial plasmodia, toxoplasma).
additional, or second intermediate hosts (eg, fish for the cat's fluke);
1) Alimentary(through the mouth with food) - helminth eggs, protozoan cysts in case of non-compliance with the rules of personal hygiene and food hygiene (vegetables, fruits); larvae of helminths (trichinella) and vegetative forms of protozoa (toxoplasma) with insufficient culinary processing of meat products.
2) Airborne(through the mucous membranes of the respiratory tract) - viruses (influenza) and bacteria (diphtheria, plague) and some protozoa (toxoplasma).
3) Contact household(direct contact with a sick person or animal, through linen and household items) - eggs of contact helminths (pinworm, dwarf tapeworm) and many arthropods (lice, scabies).
4) Transmissible- with the participation of the carrier - arthropod:
but) inoculation - through the proboscis when sucking blood (malarial plasmodia, trypanosomes);
b) contamination- when combing and rubbing excrement or carrier hemolymph into the skin (lousy typhus, plague).
Transplacental(through the placenta) - toxoplasma, malarial plasmodia.
Sexual(during sexual intercourse) - AIDS virus, Trichomonas.
Transfusion(during blood transfusion) - AIDS virus, malarial plasmodia, trypanosomes.
a) highly adapted(contradictions in the system practically do not appear);
The following forms of manifestation of specificity are distinguished:
topical: a certain localization in the host (head and body lice, scabies mite, intestinal helminths);
age(pinworms and dwarf tapeworm more often affect children);
seasonal(outbreaks of amoebic dysentery are associated with the spring-summer period, trichinosis - with the autumn-winter period).
All living beings on the planet are divided into different groups and systems. Biology tells the student about this even in the elementary grades of high school. Now I want to study in great detail the levels of organization of wildlife, as a result, presenting all the knowledge gained in a concise and easy-to-understand table.
A bit about levels
Generally speaking, science has 8 such levels. But what is the principle of division? Everything is simple here: each subsequent level incorporates all the previous ones. That is, it is larger and more substantial, more voluminous and fuller.
Level One - Molecular
This level is studied in detail by molecular biology. What is it about? What is the structure of proteins, what functions do they perform, what are nucleic acids and their work in genetics, protein synthesis, RNA and DNA - all these processes are loaded at the molecular level. It is here that the most important life processes of all organisms begin: metabolism, the production of energy necessary for existence, etc. Scientists argue that this level can hardly be called alive, it is rather considered chemical.
Level two - cellular
What is interesting about the cellular level of organization of living nature? It follows the molecular and, as the name implies, deals with cells. The biology of these particles is studied by such a science as cytology. The cell itself is the smallest indivisible particle in the human body. Here all the processes that are directly related to the vital activity of the cell are considered.
Level three - tissue
Specialists also call this level multicellular. And this is not surprising. After all, in fact, tissue is a collection of cells that have almost the same structure and similar functions. If we talk about those sciences that study this level, then we are talking about the same histology, as well as histochemistry.
Level four - organ
Considering the levels of organization of living nature, it is also necessary to talk about the organ. Why is he special? So, organs are formed from tissues in multicellular organisms and organelles in unicellular organisms. The sciences that deal with these issues are anatomy, embryology, physiology, botany and zoology.
It should also be noted that, when studying the levels of organization of living nature, experts sometimes combine tissue and organism into one chapter. After all, they are very closely related to each other. In this case, we are talking about the organ-tissue level.
Fifth level - organismal
The next level is called "organismal" in science. How is it different from the previous ones? In addition to the fact that it includes in its composition the previous levels of organization of wildlife, there is also a division into kingdoms - animals, plants, and fungi. He is involved in the following processes:
In fact, there are still a lot of functions. This section deals with such sciences as genetics, physiology, anatomy, morphology.
The sixth level - population-species
Everything is simple here too. If some organisms are morphologically similar, that is, they are approximately the same structure and have a similar genotype, scientists combine them into one species or population. The main processes that take place here are macroevolution (that is, a change in the body under the influence of the environment), as well as interaction with each other (this can be both a struggle for survival and reproduction). These processes are studied by ecology and genetics.
Seventh level - biogeocenotic
The name is difficult to pronounce, but quite simple. It comes from the word biogeocenosis. There are already considered multiple processes in which the interaction of organisms occurs. We are talking about food chains, about competition and reproduction, about the mutual influence of organisms and the environment on each other. These issues are dealt with by such a science as ecology.
The last, eighth level is biospheric
Here already biology is called upon to solve all global problems. After all, in fact, the biosphere is a huge ecosystem where the circulation of chemical elements and substances takes place, the processes of energy conversion to ensure the vital activity of all life on earth.
Simple Conclusions
Having considered all levels of the structural organization of living nature, and as it became clear, there are 8 of them, one can imagine a picture of all life on earth. After all, only by structuring your knowledge, you can thoroughly understand the essence of the above.
Organismic | Either an individual or an organism | processes of differentiation |
population-species | population | There are processes of changing the genotype in this population |
Biogeocenotic-biospheric | Biogeocenosis | The circulation of substances takes place |
Molecular genetic | Activity - the transfer of genetic information within cells |
What is the easiest way to represent the levels of organization of living nature? The table is what perfectly illustrates any material. But to facilitate understanding, scientists often put in the table only 4 combined levels presented above.
The levels of organization of the organic world are discrete states of biological systems, characterized by subordination, interconnectedness, and specific patterns.
Structural levels of life organization are extremely diverse, but the main ones are molecular, cellular, ontogenetic, population-species, biocenotic and biospheric.
1. Molecular genetic standard of living. The most important tasks of biology at this stage is the study of the mechanisms of transmission of gene information, heredity and variability.
There are several mechanisms of variability at the molecular level. The most important of them is the mechanism of gene mutation - the direct transformation of the genes themselves under the influence of external factors. The factors causing the mutation are: radiation, toxic chemical compounds, viruses.
Another mechanism of variability is gene recombination. Such a process takes place during sexual reproduction in higher organisms. In this case, there is no change in the total amount of genetic information.
Another mechanism of variability was discovered only in the 1950s. This is a non-classical recombination of genes, in which there is a general increase in the amount of genetic information due to the inclusion of new genetic elements in the cell genome. Most often, these elements are introduced into the cell by viruses.
2. Cellular level. Today, science has reliably established that the smallest independent unit of the structure, functioning and development of a living organism is a cell, which is an elementary biological system capable of self-renewal, self-reproduction and development. Cytology is a science that studies a living cell, its structure, functioning as an elementary living system, explores the functions of individual cellular components, the process of cell reproduction, adaptation to environmental conditions, etc. Cytology also studies the features of specialized cells, the formation of their special functions and the development of specific cellular structures . Thus, modern cytology has been called cell physiology.
A significant advance in the study of cells occurred at the beginning of the 19th century, when the cell nucleus was discovered and described. Based on these studies, the cellular theory was created, which became the greatest event in biology in the 19th century. It was this theory that served as the foundation for the development of embryology, physiology, and the theory of evolution.
The most important part of all cells is the nucleus, which stores and reproduces genetic information, regulates the metabolic processes in the cell.
All cells are divided into two groups:
Prokaryotes - cells lacking a nucleus
eukaryotes are cells that contain nuclei
Studying a living cell, scientists drew attention to the existence of two main types of its nutrition, which allowed all organisms to be divided into two types:
Autotrophic - produce their own nutrients
· Heterotrophic - can not do without organic food.
Later, such important factors as the ability of organisms to synthesize the necessary substances (vitamins, hormones), provide themselves with energy, dependence on the ecological environment, etc. were clarified. Thus, the complex and differentiated nature of the relationships indicates the need for a systematic approach to the study of life at the ontogenetic level. .
3. Ontogenetic level. multicellular organisms. This level arose as a result of the formation of living organisms. The basic unit of life is an individual, and the elementary phenomenon is ontogenesis. Physiology deals with the study of the functioning and development of multicellular living organisms. This science considers the mechanisms of action of various functions of a living organism, their relationship with each other, regulation and adaptation to the external environment, origin and formation in the process of evolution and individual development of an individual. In fact, this is the process of ontogenesis - the development of the organism from birth to death. In this case, growth, movement of individual structures, differentiation and complication of the organism occur.
All multicellular organisms are composed of organs and tissues. Tissues are a group of physically connected cells and intercellular substances to perform certain functions. Their study is the subject of histology.
Organs are relatively large functional units that combine various tissues into certain physiological complexes. In turn, organs are part of larger units - body systems. Among them are the nervous, digestive, cardiovascular, respiratory and other systems. Only animals have internal organs.
4. Population-biocenotic level. This is a supra-organismal level of life, the basic unit of which is the population. In contrast to a population, a species is a collection of individuals that are similar in structure and physiological properties, have a common origin, and can freely interbreed and produce fertile offspring. A species exists only through populations representing genetically open systems. Population biology is the study of populations.
The term "population" was introduced by one of the founders of genetics, V. Johansen, who called it a genetically heterogeneous set of organisms. Later, the population began to be considered an integral system, continuously interacting with the environment. It is the populations that are the real systems through which the species of living organisms exist.
Populations are genetically open systems, since the isolation of populations is not absolute and the exchange of genetic information is not possible from time to time. It is populations that act as elementary units of evolution; changes in their gene pool lead to the emergence of new species.
Populations capable of independent existence and transformation are united in the aggregate of the next supraorganismal level - biocenoses. Biocenosis - a set of populations living in a certain area.
The biocenosis is a system closed to foreign populations, for its constituent populations it is an open system.
5. Biogeocetonic level. Biogeocenosis is a stable system that can exist for a long time. Equilibrium in a living system is dynamic, i.e. represents a constant movement around a certain point of stability. For its stable functioning, it is necessary to have feedback between its control and executing subsystems. This way of maintaining a dynamic balance between various elements of biogeocenosis, caused by the mass reproduction of some species and the reduction or disappearance of others, leading to a change in the quality of the environment, is called an ecological disaster.
Biogeocenosis is an integral self-regulating system in which several types of subsystems are distinguished. Primary systems are producers that directly process inanimate matter; consumers - a secondary level at which matter and energy are obtained through the use of producers; then come second-order consumers. There are also scavengers and decomposers.
The cycle of substances passes through these levels in the biogeocenosis: life is involved in the use, processing and restoration of various structures. In biogeocenosis - a unidirectional energy flow. This makes it an open system, continuously connected with neighboring biogeocenoses.
Self-regulation of biogeocens proceeds the more successfully, the more diverse the number of its constituent elements. The stability of biogeocenoses also depends on the diversity of its components. The loss of one or more components can lead to an irreversible imbalance and its death as an integral system.
6. Biosphere level. This is the highest level of life organization, covering all the phenomena of life on our planet. The biosphere is the living substance of the planet and the environment transformed by it. Biological metabolism is a factor that unites all other levels of life organization into one biosphere. At this level, there is a circulation of substances and the transformation of energy associated with the vital activity of all living organisms living on Earth. Thus, the biosphere is a single ecological system. The study of the functioning of this system, its structure and functions is the most important task of biology at this level of life. Ecology, biocenology and biogeochemistry are engaged in the study of these problems.
The development of the doctrine of the biosphere is inextricably linked with the name of the outstanding Russian scientist V.I. Vernadsky. It was he who managed to prove the connection of the organic world of our planet, acting as a single inseparable whole, with geological processes on Earth. Vernadsky discovered and studied the biogeochemical functions of living matter.
Thanks to the biogenic migration of atoms, living matter performs its geochemical functions. Modern science identifies five geochemical functions that living matter performs.
1. The concentration function is expressed in the accumulation of certain chemical elements inside living organisms due to their activity. The result of this was the emergence of mineral reserves.
2. The transport function is closely related to the first function, since living organisms carry the chemical elements they need, which then accumulate in their habitats.
3. The energy function provides energy flows penetrating the biosphere, which makes it possible to carry out all the biogeochemical functions of living matter.
4. Destructive function - the function of destruction and processing of organic remains, during this process, the substances accumulated by organisms are returned to natural cycles, there is a cycle of substances in nature.
5. Average-forming function - transformation of the environment under the influence of living matter. The entire modern appearance of the Earth - the composition of the atmosphere, hydrosphere, upper layer of the lithosphere; most of the minerals; climate is the result of the action of Life.
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