Natalya Sergeevna Kurbatova, E. A. Kozlova

1. History of development cell theory

The prerequisites for the creation of the cell theory were the invention and improvement of the microscope and the discovery of cells (1665, R. Hooke - when studying a section of the bark of a cork tree, elderberry, etc.). The works of famous microscopists: M. Malpighi, N. Grew, A. van Leeuwenhoek - made it possible to see the cells of plant organisms. A. van Leeuwenhoek discovered single-celled organisms in water. First studied cell nucleus. R. Brown described the nucleus of a plant cell. Ya. E. Purkine introduced the concept of protoplasm - liquid gelatinous cellular contents.

The German botanist M. Schleiden was the first to come to the conclusion that every cell has a nucleus. The founder of CT is considered to be the German biologist T. Schwann (together with M. Schleiden), who in 1839 published the work “Microscopic studies on the correspondence in the structure and growth of animals and plants.” Its provisions:

1) the cell is the main structural unit of all living organisms (both animals and plants);

2) if any formation visible under a microscope has a nucleus, then it can be considered a cell;

3) the process of formation of new cells determines the growth, development, differentiation of plant and animal cells.

Additions to the cell theory were made by the German scientist R. Virchow, who in 1858 published his work “Cellular Pathology”. He proved that daughter cells are formed by dividing mother cells: each cell from a cell. IN late XIX V. mitochondria, the Golgi complex, plastids were discovered in plant cells. After staining dividing cells with special dyes, chromosomes were discovered. Modern CT provisions

1. The cell is the basic unit of structure and development of all living organisms and is the smallest structural unit alive.

2. The cells of all organisms (both unicellular and multicellular) are similar in chemical composition, structure, basic manifestations of metabolism and vital activity.

3. Cells reproduce by dividing them (each new cell formed during the division of the mother cell); in complex multicellular organisms, cells have various shapes and are specialized according to the functions performed. Similar cells form tissues; tissues consist of organs that form organ systems; they are closely interconnected and subject to nervous and humoral regulatory mechanisms (in higher organisms).

Importance of Cell Theory

It has become clear that the cell is the most important component of living organisms, their main morphophysiological component. The cell is the basis of a multicellular organism, the place where biochemical and physiological processes in the body. At the cellular level, everything ultimately happens biological processes. Cell theory allowed us to conclude that the chemical composition of all cells is similar, in general terms their structure, which confirms the phylogenetic unity of the entire living world.

2. Life. Properties of living matter

Life is a macromolecular open system, which is characterized by a hierarchical organization, the ability to reproduce itself, self-preservation and self-regulation, metabolism, and a finely regulated flow of energy.

Properties of living structures:

1) self-renewal. The basis of metabolism is made up of balanced and clearly interconnected processes of assimilation (anabolism, synthesis, formation of new substances) and dissimilation (catabolism, decay);

2) self-reproduction. In this regard, living structures are constantly reproduced and updated, without losing their similarities with previous generations. Nucleic acids are capable of storing, transmitting and reproducing hereditary information, as well as implementing it through protein synthesis. The information stored on DNA is transferred to the protein molecule using RNA molecules;

3) self-regulation. Based on the totality of flows of matter, energy and information through a living organism;

5) maintaining homeostasis - relative dynamic constancy internal environment organism, physical and chemical parameters of the system’s existence;

6) structural organization - orderliness, of a living system, discovered during the study - biogeocenoses;

7) adaptation – the ability of a living organism to constantly adapt to changing conditions of existence in the environment;

8) reproduction (reproduction). Since life exists in the form of individual living systems, and the existence of each such system is strictly limited in time, the maintenance of life on Earth is associated with the reproduction of living systems;

9) heredity. Ensures continuity between generations of organisms (based on information flows). Thanks to heredity, traits that ensure adaptation to the environment are passed on from generation to generation;

10) variability - due to variability living system acquires characteristics that were previously unusual for her. First of all, variability is associated with errors during reproduction: changes in the structure nucleic acids lead to the emergence of new hereditary information;

11) individual development (ontogenesis process) – the embodiment of the original genetic information, embedded in the structure of DNA molecules, in the working structures of the body. During this process, such a property as the ability to grow appears, which is expressed in an increase in body weight and its size;

12) phylogenetic development. Based on progressive reproduction, heredity, struggle for existence and selection. As a result of evolution, it appeared huge amount species;

3. Levels of life organization

Living nature is holistic, but heterogeneous system, which is characterized by a hierarchical organization. Hierarchical is a system in which parts (or elements of the whole) are arranged in order from highest to lowest.

Microsystems (pre-organismal stage) include molecular (molecular-genetic) and subcellular levels.

Mesosystems (organismal stage) include cellular, tissue, organ, systemic, organismal (the organism as a whole), or ontogenetic levels.

Macrosystems (superorganismal stage) include population-species, biocenotic and global levels (biosphere as a whole). At each level it is possible to distinguish elementary unit and phenomenon.

An elementary unit (EU) is a structure (or object), the regular changes of which (elementary phenomena, UE) constitute its contribution to the development of life at a given level.

Hierarchical levels:

1) molecular genetic level. EE is represented by the genome. A gene is a section of a DNA molecule (and in some viruses, an RNA molecule) that is responsible for the formation of any one trait;

2) sub cellular level. The EE is represented by some subcellular structure, i.e., an organelle that performs its inherent functions and contributes to the functioning of the cell as a whole;

3) cellular level. EE is a cell that is an independently functioning elementary

The prerequisites for the creation of the cell theory were the invention and improvement of the microscope and the discovery of cells (1665, R. Hooke - when studying a section of the bark of a cork tree, elderberry, etc.). The works of famous microscopists: M. Malpighi, N. Grew, A. van Leeuwenhoek - made it possible to see the cells of plant organisms. A. van Leeuwenhoek discovered single-celled organisms in water. First, the cell nucleus was studied. R. Brown described the nucleus of a plant cell. Ya. E. Purkine introduced the concept of protoplasm - liquid gelatinous cellular contents.

1) the cell is the main structural unit of all living organisms (both animals and plants);

2) if any formation visible under a microscope has a nucleus, then it can be considered a cell;

3) the process of formation of new cells determines the growth, development, differentiation of plant and animal cells. Additions to the cell theory were made by the German scientist R. Virchow, who in 1858 published his work “Cellular Pathology”. He proved that daughter cells are formed by dividing mother cells: each cell from a cell. At the end of the 19th century. mitochondria, the Golgi complex, and plastids were discovered in plant cells. After staining dividing cells with special dyes, chromosomes were discovered. Modern CT provisions

1. The cell is the basic unit of structure and development of all living organisms, and is the smallest structural unit of a living thing.

2. The cells of all organisms (both unicellular and multicellular) are similar in chemical composition, structure, basic manifestations of metabolism and vital activity.

3. Cells reproduce by dividing them (each new cell is formed by dividing the mother cell); In complex multicellular organisms, cells have different shapes and are specialized according to the functions they perform. Similar cells form tissues; tissues consist of organs that form organ systems; they are closely interconnected and subject to nervous and humoral regulatory mechanisms (in higher organisms).

Importance of Cell Theory

It has become clear that the cell is the most important component of living organisms, their main morphophysiological component. A cell is the basis of a multicellular organism, the place where biochemical and physiological processes occur in the body. All biological processes ultimately occur at the cellular level. The cellular theory made it possible to conclude that the chemical composition of all cells and the general plan of their structure are similar, which confirms the phylogenetic unity of the entire living world.

2. Definition of life at the present stage of scientific development

It is quite difficult to give a complete and unambiguous definition the concept of life, given the huge variety of its manifestations. Most definitions of the concept of life, which were given by many scientists and thinkers over the centuries, took into account the leading qualities that distinguish living from non-living. For example, Aristotle said that life is the “nutrition, growth and decrepitude” of the body; A. L. Lavoisier defined life as “ chemical function"; G. R. Treviranus believed that life is “a stable uniformity of processes with differences external influences" It is clear that such definitions could not satisfy scientists, since they did not (and could not reflect) all the properties of living matter. In addition, observations indicate that the properties of living things are not exceptional and unique, as it seemed before; they are separately found among inanimate objects. A.I. Oparin defined life as “special, very complex shape movement of matter." This definition reflects the qualitative uniqueness of life, which cannot be reduced to simple chemical or physical laws. However, in this case too the definition is general character and does not reveal the specific originality of this movement.

F. Engels wrote in “Dialectics of Nature”: “Life is a way of existence of protein bodies, the essential point of which is the exchange of matter and energy with environment».

For practical application Those definitions that contain the basic properties that are necessarily inherent in all living forms are useful. Here is one of them: life is a macromolecular open system, which is characterized by a hierarchical organization, the ability to reproduce itself, self-preservation and self-regulation, metabolism, and a finely regulated flow of energy. According to this definition life is a core of order spreading through a less ordered universe.

Life exists in form open systems. This means that any living form is not closed only on itself, but constantly exchanges matter, energy and information with the environment.

3. Fundamental properties of living matter

These properties collectively characterize any living system and life in general:

1) self-renewal. Associated with the flow of matter and energy. Metabolism is based on balanced and clearly interconnected processes of assimilation (anabolism, synthesis, formation of new substances) and dissimilation (catabolism, decay). As a result of assimilation, the structures of the body are renewed and new parts (cells, tissues, parts of organs) are formed. Dissimilation determines the breakdown of organic compounds and provides the cell with plastic matter and energy. For the formation of a new one, a constant influx of necessary substances from the outside is needed, and in the process of life activity (and dissimilation, in particular) products are formed that need to be released into the external environment;

2) self-reproduction. Ensures continuity between changing generations of biological systems. This property is associated with the flow of information embedded in the structure of nucleic acids. In this regard, living structures are constantly reproduced and updated, without losing their resemblance to previous generations (despite the continuous renewal of matter). Nucleic acids are capable of storing, transmitting and reproducing hereditary information, as well as implementing it through protein synthesis. The information stored on DNA is transferred to the protein molecule using RNA molecules;

3) self-regulation. Based on the totality of flows of matter, energy and information through a living organism;

4) irritability. Associated with the transfer of information from the outside to any biological system and reflects the reaction of this system to an external stimulus. Thanks to irritability, living organisms are able to selectively respond to environmental conditions and extract from it only what is necessary for their existence. Self-regulation of living systems is associated with irritability according to the principle feedback: waste products can have an inhibitory or stimulating effect on those enzymes that were at the beginning long chain chemical reactions;

5) maintaining homeostasis (from the gr. homoios - “similar, identical” and stasis - “immobility, state”) - the relative dynamic constancy of the internal environment of the body, the physico-chemical parameters of the existence of the system;

6) structural organization - a certain orderliness, harmony of a living system. It is discovered during the study of not only individual living organisms, but also their aggregates in connection with the environment - biogeocenoses;

7) adaptation – the ability of a living organism to constantly adapt to changing conditions of existence in the environment. It is based on irritability and its characteristic adequate responses;

1. Cell theory (CT) Prerequisites of cell theory

The prerequisites for the creation of the cell theory were the invention and improvement of the microscope and the discovery of cells (1665, R. Hooke - when studying a section of the bark of a cork tree, elderberry, etc.). The works of famous microscopists: M. Malpighi, N. Grew, A. van Leeuwenhoek - made it possible to see the cells of plant organisms. A. van Leeuwenhoek discovered single-celled organisms in water. First, the cell nucleus was studied. R. Brown described the nucleus of a plant cell. Ya. E. Purkine introduced the concept of protoplasm - liquid gelatinous cellular contents.

1) the cell is the main structural unit of all living organisms (both animals and plants);

2) if any formation visible under a microscope has a nucleus, then it can be considered a cell;

1. The cell is the basic unit of structure and development of all living organisms, and is the smallest structural unit of a living thing.

2. The cells of all organisms (both unicellular and multicellular) are similar in chemical composition, structure, basic manifestations of metabolism and vital activity.

Importance of Cell Theory

2. Definition of life on modern stage development of science

It is quite difficult to give a complete and unambiguous definition of the concept of life, given the huge variety of its manifestations.

Most definitions of the concept of life, which were given by many scientists and thinkers over the centuries, took into account the leading qualities that distinguish living from non-living. For example, Aristotle said that life is the “nutrition, growth and decrepitude” of the body; A. L. Lavoisier defined life as a “chemical function”; G. R. Treviranus believed that life is “a stable uniformity of processes with differences in external influences.” It is clear that such definitions could not satisfy scientists, since they did not (and could not reflect) all the properties of living matter. In addition, observations indicate that the properties of the living are not exceptional and unique, as it seemed before; they are separately found among inanimate objects. A.I. Oparin defined life as “a special, very complex form of movement of matter.” This definition reflects the qualitative uniqueness of life, which cannot be reduced to simple chemical or physical laws. However, even in this case, the definition is of a general nature and does not reveal the specific uniqueness of this movement.

F. Engels wrote in “Dialectics of Nature”: “Life is a way of existence of protein bodies, the essential point of which is the exchange of matter and energy with the environment.”

For practical application, those definitions that contain the basic properties that are necessarily inherent in all living forms are useful. Here is one of them: life is a macromolecular open system, which is characterized by a hierarchical organization, the ability to reproduce itself, self-preservation and self-regulation, metabolism, and a finely regulated flow of energy. By this definition, life is a core of order spreading through a less ordered universe.

Life exists in the form of open systems. This means that any living form is not closed only on itself, but constantly exchanges matter, energy and information with the environment.

3. Fundamental Properties living matter

These properties collectively characterize any living system and life in general:

3) self-regulation. Based on the totality of flows of matter, energy and information through a living organism;

4) irritability. Associated with the transfer of information from the outside to any biological system and reflects the reaction of this system to an external stimulus. Thanks to irritability, living organisms are able to selectively respond to environmental conditions and extract from it only what is necessary for their existence. Irritability is associated with self-regulation of living systems based on the feedback principle: waste products can have an inhibitory or stimulating effect on those enzymes that were at the beginning of a long chain of chemical reactions;

7) adaptation – the ability of a living organism to constantly adapt to changing conditions of existence in the environment. It is based on irritability and its characteristic adequate responses;

8) reproduction (reproduction). Since life exists in the form of separate (discrete) living systems (for example, cells), and the existence of each such system is strictly limited in time, the maintenance of life on Earth is associated with the reproduction of living systems. On molecular level reproduction is carried out thanks to matrix synthesis, new molecules are formed according to the program embedded in the structure (matrix) of pre-existing molecules;

9) heredity. Ensures continuity between generations of organisms (based on information flows).

Closely related to the autoreproduction of life at the molecular, subcellular and cellular levels. Thanks to heredity, traits that ensure adaptation to the environment are passed on from generation to generation;

10) variability is a property opposite to heredity. Due to variability, a living system acquires characteristics that were previously unusual for it. First of all, variability is associated with errors during reproduction: changes in the structure of nucleic acids lead to the emergence of new hereditary information. New signs and properties appear. If they are useful for the organism in a given environment, then they are picked up and fixed by natural selection. New forms and types are being created. Thus, variability creates the prerequisites for speciation and evolution;

11) individual development (the process of ontogenesis) - the embodiment of the initial genetic information embedded in the structure of DNA molecules (i.e., in the genotype) into the working structures of the body. During this process, a property such as the ability to grow manifests itself, which is expressed in an increase in body weight and its size. This process is based on the reproduction of molecules, reproduction, growth and differentiation of cells and other structures, etc.;

12) phylogenetic development (its patterns were established by C. R. Darwin). Based on progressive reproduction, heredity, struggle for existence and selection. As a result of evolution, a huge number of species appeared. Progressive evolution has passed through a number of stages. These are pre-cellular, unicellular and multicellular organisms up to humans.

At the same time, human ontogenesis repeats phylogeny (i.e., individual development goes through the same stages as the evolutionary process);

13) discreteness (discontinuity) and at the same time integrity. Life is represented by a collection of individual organisms, or individuals. Each organism, in turn, is also discrete, since it consists of a collection of organs, tissues and cells. Each cell consists of organelles, but at the same time is autonomous. Hereditary information is carried out by genes, but no single gene can determine the development of a particular trait.

4. Levels of life organization

Living nature is an integral, but heterogeneous system, which is characterized by a hierarchical organization. Hierarchical is a system in which parts (or elements of the whole) are arranged in order from highest to lowest. The hierarchical principle of organization makes it possible to distinguish in living nature separate levels, which is very convenient when studying life as a complex natural phenomenon. We can distinguish three main stages of living things: microsystems, mesosystems and macrosystems.

Microsystems (pre-organismal stage) include molecular (molecular-genetic) and subcellular levels.

Mesosystems (organismal stage) include cellular, tissue, organ, systemic, organismal (the organism as a whole), or ontogenetic levels.

Macrosystems (superorganismal stage) include population-species, biocenotic and global levels (biosphere as a whole). At each level one can distinguish an elementary unit and a phenomenon.

An elementary unit (EU) is a structure (or object), the regular changes of which (elementary phenomena, UE) constitute its contribution to the development of life at a given level.

Hierarchical levels:

1) molecular genetic level. EE is represented by the genome. A gene is a section of a DNA molecule (and in some viruses, an RNA molecule) that is responsible for the formation of any one trait. The information contained in nucleic acids is realized through matrix synthesis proteins;

2) subcellular level. The EE is represented by some subcellular structure, i.e., an organelle that performs its inherent functions and contributes to the functioning of the cell as a whole;

3) cellular level. EE is a cell that is an independently functioning elementary biological system. Only at this level are the implementation of genetic information and biosynthesis processes possible. For single-celled organisms this level coincides with the organism level. EA are reactions cellular metabolism, forming the basis of flows of energy, information and matter;

4) tissue level. A collection of cells with the same type of organization constitutes tissue (TE). The level arose with the advent multicellular organisms with more or less differentiated tissues. The tissue functions as a single whole and has the properties of a living thing;

5) organ level. Formed together with functioning cells belonging to different tissues(EE). A total of four main tissues make up the organs of multicellular organisms; six main tissues form the organs of plants;

6) organismal (ontogenetic) level. EE is an individual in its development from the moment of birth until the end of its existence as a living system. EI are natural changes in the body in the process individual development(ontogenesis). In the process of ontogenesis, under certain environmental conditions, the embodiment of hereditary information occurs biological structures, i.e., based on the genotype of an individual, its phenotype is formed;

7) population-species level. EE is a population, i.e. a collection of individuals (organisms) of the same species inhabiting one territory and freely interbreeding with each other. A population has a gene pool, i.e., a set of genotypes of all individuals. Impact on the gene pool of elementary evolutionary factors(mutations, fluctuations in the number of individuals, natural selection) leads to evolutionarily significant changes (ES);

8) biocenotic (ecosystem) level. EE – biocenosis, i.e. historically established stable community of populations different types, connected with each other and with the surrounding inanimate nature by the exchange of substances, energy and information (cycles), which constitute EE;

9) biosphere (global) level. EE – biosphere (the area of distribution of life on Earth), i.e. a single planetary complex of biogeocenoses, different in species composition and characteristics of the abiotic (non-living) part. Biogeocenoses determine all processes occurring in the biosphere;

10) nospheric level. This new concept was formulated by Academician V.I. Vernadsky. He founded the doctrine of the noosphere as the sphere of the mind. This component biosphere that has been modified by human activity.

LECTURE No. 2. Chemical composition of living systems. Biological role of proteins, polysaccharides, lipids and ATP

1. Review chemical structure cells

All living systems contain different ratios chemical elements and the chemical compounds constructed from them, both organic and inorganic.

Based on their quantitative content in the cell, all chemical elements are divided into 3 groups: macro-, micro- and ultra-microelements.

Macroelements make up up to 99% of the cell's mass, of which up to 98% comes from 4 elements: oxygen, nitrogen, hydrogen and carbon. In smaller quantities, cells contain potassium, sodium, magnesium, calcium, sulfur, phosphorus, and iron.

Microelements are mainly metal ions (cobalt, copper, zinc, etc.) and halogens (iodine, bromine, etc.). They are contained in quantities from 0.001% to 0.000001%.

Ultramicroelements. Their concentration is below 0.000001%. These include gold, mercury, selenium, etc.

A chemical compound is a substance in which the atoms of one or more chemical elements are connected to each other through chemical bonds. Chemical compounds There are inorganic and organic. Inorganic include water and mineral salts. Organic compounds are compounds of carbon with other elements.

The main organic compounds of the cell are proteins, fats, carbohydrates and nucleic acids.

2. Biopolymers Proteins

These are polymers whose monomers are amino acids. They are mainly composed of carbon, hydrogen, oxygen and nitrogen. A protein molecule can have 4 levels of structural organization (primary, secondary, tertiary and quaternary structures).

Functions of proteins:

1) protective (interferon is intensively synthesized in the body during a viral infection);

2) structural (collagen is part of tissues and participates in scar formation);

3) motor (myosin is involved in muscle contraction);

4) spare (egg albumin);

5) transport (hemoglobin in erythrocytes transports nutrients and metabolic products);

6) receptor (receptor proteins ensure that the cell recognizes substances and other cells);

7) regulatory (regulatory proteins determine the activity of genes);

8) hormone proteins are involved in humoral regulation(insulin regulates blood sugar levels);

9) enzyme proteins catalyze everything chemical reactions in the body;

10) energy (with the breakdown of 1 g of protein, 17 kJ of energy is released).

Carbohydrates

These are mono- and polymers, which contain carbon, hydrogen and oxygen in a ratio of 1: 2: 1.

Functions of carbohydrates:

1) energy (with the breakdown of 1 g of carbohydrates, 17.6 kJ of energy is released);

2) structural (cellulose, which is part of the cell wall of plants);

3) storage (reserve nutrients in the form of starch in plants and glycogen in animals).

Fats (lipids) can be simple or complex. Simple lipid molecules consist of the trihydric alcohol glycerol and three fatty acid residues. Complex lipids are compounds of simple lipids with proteins and carbohydrates.

Functions of lipids:

1) energy (the breakdown of 1 g of lipids produces 38.9 kJ of energy);

2) structural (phospholipids cell membranes, forming a lipid bilayer);

3) storage (storage of nutrients in subcutaneous tissue and other organs);

4) protective (subcutaneous tissue and a layer of fat around internal organs protect them from mechanical damage);

5) regulatory (hormones and vitamins containing lipids regulate metabolism);

6) heat-insulating (subcutaneous tissue retains heat). ATP

The ATP (adenosine triphosphoric acid) molecule consists of the nitrogenous base adenine, the five-carbon sugar ribose and three phosphoric acid residues connected by a high-energy bond. ATP is produced in mitochondria through the process of phosphorylation. Upon its hydrolysis, it is released large number energy. ATP is the main macroerg of the cell - an energy accumulator in the form of the energy of high-energy chemical bonds.

LECTURE No. 3. Nucleic acids. Protein biosynthesis

Nucleic acids are phosphorus-containing biopolymers, the monomers of which are nucleotides. Nucleic acid chains include from several tens to hundreds of millions of nucleotides.

There are 2 types of nucleic acids – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The nucleotides that make up DNA contain the carbohydrate deoxyribose, and the nucleotides that make up RNA contain ribose.

1. DNA

Typically, DNA is a helix consisting of two complementary polynucleotide chains twisted to the right. DNA nucleotides include: a nitrogenous base, deoxyribose and a phosphoric acid residue. Nitrogen bases are divided into purine (adenine and guanine) and pyrimidine (thymine and cytosine). Two chains of nucleotides are connected to each other through nitrogenous bases according to the principle of complementarity: two hydrogen bonds arise between adenine and thymine, and three between guanine and cytosine.

Functions of DNA:

1) ensures the preservation and transmission of genetic information from cell to cell and from organism to organism, which is associated with its ability to replicate;

2) regulation of all processes occurring in the cell, provided by the ability of transcription followed by translation.

The process of self-reproduction (auto-reproduction) of DNA is called replication. Replication ensures the copying of genetic information and its transmission from generation to generation, the genetic identity of daughter cells formed as a result of mitosis, and the constancy of the number of chromosomes during mitotic cell division.

Replication occurs during the synthetic period of interphase of mitosis. The replicase enzyme moves between the two strands of the DNA helix and breaks the hydrogen bonds between nitrogenous bases. Then, using the enzyme DNA polymerase, the nucleotides of the daughter chains are added to each of the chains according to the principle of complementarity. As a result of replication, two identical DNA molecules are formed. The amount of DNA in the cell doubles. This method of DNA doubling is called semi-conservative, since each new DNA molecule contains one “old” and one newly synthesized polynucleotide chain.

The textbook reflects current state science about the general laws of the origin and development of life on Earth. Part I of the textbook includes sections: “Introduction”, “Life as natural phenomenon", "Cell Biology", "Reproduction of Organisms", "Organization of Hereditary Material", "Patterns of Inheritance" and "Variability".
The textbook is intended for university students studying biological, medical and agricultural specialties.

Properties of living things.
Living organisms, as opposed to bodies inanimate nature, are characterized by a number of properties that are, in fact, attributes of life: orderliness and specificity of structure, integrity and discreteness, self-regulation and homeostasis, self-reproduction and self-healing, heredity and variability, metabolism and energy, growth and development, irritability, movement, self-regulation, specific relationship with the environment, aging and death, involvement in continuous process historical changes living (evolutionary process). These attributes of life are the objects of research of many independent biological sciences, the results of which are presented below in various sections of the textbook. However, some of them are reasonably considered fundamental and require special consideration at the beginning of the “General Biology” course.

Orderliness and specificity of structure. Living organisms contain the same chemical elements as living things. However, in the cells of living beings they are found in the form of not only inorganic, but also organic compounds. In addition, the form of existence of living things has very significant specific features, primarily the complexity and orderliness that distinguish both the molecular and supramolecular levels of organization. Creating order - most important property alive. Orderliness in space is accompanied by orderliness in time.

Table of contents
INTRODUCTION 3
CHAPTER 1. LIFE AS A NATURAL PHENOMENON 9
1.1. Defining the essence of life 9
1.2. Substrate of life 10
1.3. Properties of living things 11
1.4. Fundamental properties of life 12
1.5. Levels of life organization 13
CHAPTER2. CELL BIOLOGY 16
2.1. The cell is the elementary structural, functional and genetic unit of life 16
2.2. The main stages of development and the current state of cell theory 16
2.3. Structural organization prokaryotic and eukaryotic cells 20
2.4. Surface apparatus of cell 23
2.5. Cytoplasmic apparatus of cell 30
2.5.1. Hyaloplasma 30
2.5.2. Organelles (organoids) of cells 32
2.5.2.1. Membrane organelles (organelles) 34
2.5.2.2. Non-membrane organelles (organelles) 41
2.6. Cell nuclear apparatus 49
2.7. Cell life cycle 55
2.7.1. Concept of life cycle cells 55
2.7.2. Interphase 56
2.7.2.1. Postmitotic period 57
2.7.2.2. Synthetic period. Self-Duplication of DNA 57
2.7.2.3. Premitotic period 64
2.7.2.4. Mitotic period 65
2.7.2.5. Cell renewal in cell populations 69
2.7.2.6. Cell response to adverse effects 70
2.7.2.7. Cell dystrophy 70
CHAPTER 3. REPRODUCTION OF ORGANISMS 73
3.1. Reproduction is a universal property of living things. Evolution of Reproduction 73
3.2. Asexual reproduction 73
3.2.1. Monocytogenic asexual reproduction 73
3.2.2. Polycytogenic asexual reproduction 75
3.3. Sexual reproduction 76
3.3.1. Evolution of methods of sexual reproduction 77
3.3.2. Gametogenesis 82
3.3.3. Fertilization 91
3.4. Ways of interspecific exchange of biological information 92
3.5. Biological aspects sexual dimorphism 95
CHAPTER 4. ORGANIZATION OF HEREDITARY MATERIAL 97
4.1. Subject, tasks and methods of genetics. Stages of genetic development 97
4.2. Structural and functional levels of organization of hereditary material 100
4.3. Gene as a functional unit of heredity. Classification, properties and localization of genes 102
4.4. Basic provisions chromosome theory heredity 108
CHAPTER 5. PATTERNS OF INHERITANCE
5.1. Heredity as a property of ensuring material continuity between generations 110
5.2. Types and patterns of inheritance 111
5.3. Phenotype as a result of the implementation of a genotype under certain environmental conditions 117
5.4. Molecular biological concepts of the structure and functioning of genes. Gene expression and its regulation 118
5.5. Gene interaction 122
5.5.1. Interaction allelic genes 122
5.5.2. Interaction of non-allelic genes 125
5.6. Pleiotropy 129
5.7. Multiple allelism 131
5.8. Expressiveness and penetrance. Genocopies 133
5.9. Genetic engineering 134
CHAPTER 6. VARIABILITY 137
6.1. Variability as a universal property of living things 137
6.2. Modification variability, its adaptive nature, the significance of ontogenesis and evolution 138
6.3. Statistical methods studying modification variability 143
6.4. Genotypic variability. Mechanisms and biological 146.

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MINISTRY OF EDUCATION AND SCIENCE

RUSSIAN FEDERATION

FEDERAL STATE BUDGET EDUCATIONAL INSTITUTION

HIGHER PROFESSIONAL EDUCATION

"VYATSK STATE UNIVERSITY"

Faculty of Biology

Department of Microbiology

I.V. DARMOV

General biology

Course of lectures

Tutorial

Approved by the editorial and publishing commission of the methodological council of the Federal State Budgetary Educational Institution of Higher Professional Education "VyatGU" as a teaching aid for students of the direction 020400.62 "Biology" of all training profiles

Reviewers:

Associate Professor, Department of Biotechnology, Vyatka State University,

Candidate of Biological Sciences O. N. Shupletsova;

Chief Researcher of the Research Center 33 Central Research Institute of the Ministry of Defense of the Russian Federation, Kirov, Doctor of Biological Sciences, Professor V.B. Kalininsky

Darmov, I.V.

UDC 573(07)

The textbook is intended for students of the direction 020400.62 “Biology” of all training profiles studying the discipline “General Biology”.

Those. editor E.V. Kaygorodtseva

1.Biology as a science. Properties of living systems……………………………...4

2.Basics of cytology. Prokaryotes……………………………………………………..17

3.Basics of cytology. Eukaryotes. Membrane components…………….21

4.Basics of cytology. Eukaryotes. Non-membrane components…....……..29

5.Asexual reproduction. Mitosis………………………………………………………..34

6. Sexual reproduction. Meiosis………………………...………………………43

7. Basic patterns of heredity……………………...……54

8. Main patterns of variability……………………………...…64

9.Biological diversity…………………………………………….79

List of sources used……………………………….…….105

Lecture No. 1

Lecture topic: Biology as a science . Properties of living systems.

Lecture outline:

1. Biology as a science

2. Methods of biology

3. Basic concepts of biology

4. Levels of organization of living things

5. Basic properties of living systems

6. Modern definition of a living organism and life

1. Biology as a science

Biology (Greek bios- life, logos- word, doctrine) - a set of sciences about life, about living nature. Biology subject - structure of living organisms, their functions, origin, development, relationships with the environment. Along with physics, chemistry, astronomy, geology, etc. refers to natural sciences.

Biology is one of the oldest sciences, although this term appeared only in 1797 (its author was the German professor of anatomy T. Ruz (1771-1803). Aristotle (384-322 BC) is often called the "Father of Biology" belongs to the first classification of animals.

What are peculiarities biology as a science?

1.1 Biology closely associated with philosophy. This is due to the fact that of the 3 fundamental problems of natural science, 2 are the subject of biological research.

1. The problem of the origin of the Universe, space, nature in general (physics and astronomy deal with it).

2. The problem of the origin of life, i.e. living from non-living.

3. The problem of the origin of Reason and man as its carrier.

The solution to these issues is closely related to the solution fundamental question of philosophy: what comes first – matter or consciousness? Therefore, philosophical aspects occupy a significant place in biology.

1.2. The connection between biology and social and ethical issues.

Social Darwinism, for example, transfers the concept of “natural selection” to human society; differences between classes are explained by biological factors.

Other examples: racism, organ transplants, aging.

1.3. Deep specialization biology.

As a result of differentiation of biology by object of study private biological sciences arose: botany, zoology, microbiology (bacteriology, virology, mycology, etc.).

Another division of biological sciences is by levels of organization and properties of living matter: genetics (heredity), cytology (cellular level), anatomy and physiology (structure and functioning of organisms), ecology (relationships of organisms with the environment), etc.

As a result integration with other sciences arose: biochemistry, biophysics, radiobiology, space biology, etc.

Those. biology is a complex of sciences, and general biology is studying the most general patterns structure, life activity, development, origin of living organisms. The main question question that general biology is trying to answer is, what is life?

1.4. Currently, biology, while remaining theoretical basis knowledge of living things becomes directly productive force , gives rise to new technologies: biotechnology, genetic and cellular engineering, etc.