Work plan:

1. The concept of biology, its connection with other sciences………………..2

14. Features of the structure of a plant cell……………………7

30. Penetration of nutrients into the cell. The concept of turgor, plasmolysis, plasmolysis of microorganisms………………...13

45. Antibiotics and inhibitory substances. Routes of entry and their influence on the quality of milk. Measures to prevent them from getting into milk………………………………………………………15

50. Microflora of plants and feed………………………………...18

66. Characterize the causative agents of tuberculosis and brucellosis…..22

1. The concept of biology, its connection with other sciences.

Science is a field of research activity aimed at obtaining new knowledge about objects and phenomena. Science includes knowledge about the subject of study, its main task is to understand it more fully and deeply. The main function of science is research. The subject of research into biology teaching methods is the theory and practice of teaching, educating and developing students in this subject.

The methodology of teaching biology, like any science, learns the objective laws of the processes and phenomena that it studies. Identifying their general patterns allows her to explain and predict the course of events and act purposefully.

The main features of science, as a rule, are the goals, the subject of its study, methods of cognition and forms of expression of knowledge (in the form of fundamental scientific provisions, principles, laws, patterns, theories and facts, terms). The history of the formation and development of science and the names of scientists who enriched it with their discoveries are also important.

The goals facing the methodology of teaching biology lie in line with general pedagogical goals and objectives. Therefore, this methodology is a special area of ​​pedagogy, determined by the specifics of the subject of research.

The methodology for teaching biology is based on general pedagogical principles in relation to the study of biological material. At the same time, it integrates special (natural science and biological), psychological, pedagogical, ideological, cultural and other professional and pedagogical knowledge, skills and attitudes.

The methodology for teaching biology determines the goals of education, the content of the subject “Biology” and the principles of its selection.

The goals of education, along with the content, process and result of education, are an important element of any pedagogical system. Education takes into account both social goals and individual goals. Social goals are determined by the needs of a developing society. Personal goals take into account individual abilities, interests, educational needs, and self-education.

Level of education, i.e. mastery of biological knowledge, skills and abilities that contribute to active and full inclusion in educational, labor, and social activities;

Level of education, characterizing the system of worldviews, beliefs, attitude towards the surrounding world, nature, society, personality;

The level of development that determines abilities, the need for self-development and improvement of physical and mental qualities. The goal of general secondary biological education is determined taking into account these values ​​and factors such as:

Integrity of the human personality;

Predictiveness, i.e. the orientation of the goals of biological education towards modern and future biological and educational values. Thus, general secondary biological education becomes more open to updating and adjustment;

Continuity in the system of lifelong education.

The methodology for teaching biology also notes that one of the most important goals of biological education is the formation of a scientific worldview based on the integrity and unity of nature, its systemic and level construction, diversity, and the unity of man and nature. In addition, biology is focused on the formation of knowledge about the structure and functioning of biological systems, about the sustainable development of nature and society in their interaction.

The object and subject of research are the most important concepts of any science. They represent philosophical categories. The object expresses the content of reality, independent of the observer.

The objects of scientific knowledge are various aspects, properties and relationships of an object recorded in experience and included in the process of practical activity. The object of study of biology teaching methods is the teaching and educational (educational) process associated with this subject. The subject of the research methodology is the goals and content of the educational process, methods, means and forms of teaching, education and development of students.

In the development of science, its practical application and assessment of achievements, a fairly significant role belongs to the methods of scientific research. They are a means of understanding the subject being studied and a way to achieve the goal. The leading methods of teaching biology are the following: observation, pedagogical experiment, modeling, forecasting, testing, qualitative and quantitative analysis of pedagogical achievements. These methods are based on experience and sensory knowledge. However, empirical knowledge is not the only source of reliable knowledge. Methods of theoretical knowledge such as systematization, integration, differentiation, abstraction, idealization, system analysis, comparison, generalization help to identify the essence of an object and phenomenon, their internal connections.

The content structure of the biology teaching methodology is scientifically substantiated. It is divided into general and private, or special, teaching methods: natural history, courses “Plants. Bacteria. Fungi and Lichens”, in the course “Animals”, in the courses “Man”, “General Biology”.

The general methodology of teaching biology considers the main issues of all biological courses: concepts of biological education, goals, objectives, principles, methods, means, forms, models of implementation, content and structures, phasing, continuity, history of the formation and development of biological education in the country and the world; worldview, moral and eco-cultural education in the learning process; unity of content and teaching methods; relationship between forms of educational work; the integrity and development of all elements of the biological education system, which ensures the strength and awareness of knowledge, skills and abilities.

Private methods explore educational issues specific to each course, depending on the content of the educational material and the age of the students.

The general methodology of teaching biology is closely related to all particular biological methods. Its theoretical conclusions are based on private methodological research. And they, in turn, are guided by general methodological provisions for each training course. Thus, the methodology as a science is unified; it inextricably combines general and special parts.

RELATIONSHIP OF BIOLOGY TEACHING METHODS WITH OTHER SCIENCES.

The methodology of teaching biology, being a pedagogical science, is inextricably linked with didactics. This is a section of pedagogy that studies the patterns of acquisition of knowledge, skills and abilities and the formation of students’ beliefs. Didactics develops educational theory and teaching principles common to all subjects. The methodology of teaching biology, which has long been established as an independent field of pedagogy, develops theoretical and practical problems of content, forms, methods and means of teaching and education, determined by the specifics of biology.

It should be noted that didactics, on the one hand, relies in its development on the theory and practice of methodology (not only biology, but also other educational subjects), and on the other hand, it provides general scientific approaches to research in the field of methodology, ensuring the unity of methodological principles in study of the learning process.

The methodology of teaching biology is in close relationship with psychology, since it is based on the age characteristics of children. The methodology emphasizes that educational teaching can only be effective if it corresponds to the age development of students.

Biology teaching methods are closely related to biological science. The subject "Biology" is synthetic in nature. It reflects almost all the main areas of biology: botany, zoology, physiology of plants, animals and humans, cytology, genetics, ecology, evolutionary theory, the origin of life, anthropogenesis, etc. For the correct scientific explanation of natural phenomena, recognition of plants, fungi, animals in nature, their definition, preparation and experimentation require good theoretical and practical preparation.

The goal of biological science is to gain new knowledge about nature through research. The purpose of the subject “Biology” is to provide students with knowledge (facts, patterns) obtained by biological science.

The methodology of teaching biology is closely related to philosophy. It promotes the development of human self-knowledge, understanding the place and role of scientific discoveries in the system of the overall development of human culture, and allows us to connect disparate fragments of knowledge into a single scientific picture of the world. Philosophy is the theoretical basis of the methodology, equipping it with a scientific approach to the diverse aspects of training, education and development.

The connection between the methodology and philosophy is all the more important since the study of the fundamentals of the science of biology about all possible manifestations of living matter at different levels of its organization aims to form and develop a materialistic worldview. The methodology of teaching biology solves this important problem gradually, from course to course, with the expansion and deepening of biological knowledge, leading students to an understanding of natural phenomena, the movement and development of matter, and the surrounding world.

14. Features of the structure of a plant cell.

A plant cell has a nucleus and all the organelles found in an animal cell: the endoplasmic reticulum, ribosomes, mitochondria, and the Golgi apparatus. However, it differs from an animal cell in the following structural features:

1) a strong cell wall of considerable thickness;

2) special organelles - plastids, in which the primary synthesis of organic substances from minerals occurs due to light energy - photosynthesis;

3) a developed system of vacuoles, which largely determine the osmotic properties of cells.

A plant cell, like an animal cell, is surrounded by a cytoplasmic membrane, but, in addition, it is limited by a thick cell wall consisting of cellulose. The presence of a cell wall is a specific feature of plants. She determined the low mobility of plants. As a result, the nutrition and respiration of the body began to depend on the surface of the body in contact with the environment, which led in the process of evolution to a greater dismemberment of the body, much more pronounced than in animals. The cell wall has pores through which the channels of the endoplasmic reticulum of neighboring cells communicate with each other.

The predominance of synthetic processes over processes of energy release is one of the most characteristic features of the metabolism of plant organisms. The primary synthesis of carbohydrates from inorganic substances occurs in plastids.

There are three types of plastids:

1) leucoplasts - colorless plastids in which starch is synthesized from monosaccharides and disaccharides (there are leucoplasts that store proteins or fats);

2) chloroplasts - green plastids containing the pigment chlorophyll, where photosynthesis occurs - the process of formation of organic molecules from inorganic ones due to light energy,

3) chromoplasts, including various pigments from the group of carotenoids, which determine the bright color of flowers and fruits. Plastids can transform into each other. They contain DNA and RNA, and their number increases by dividing in two.

Vacuoles are surrounded by a membrane and recede from the endoplasmic reticulum. Vacuoles contain dissolved proteins, carbohydrates, low molecular weight synthesis products, vitamins, and various salts. The osmotic pressure created by substances dissolved in the vacuolar sap causes water to enter the cell, which causes turgor - the tense state of the cell wall. Thick elastic walls Cytology (from cyto... and... logy) is the science of cells. Studies the structure and functions of cells, their connections and relationships in organs and tissues of multicellular organisms, as well as unicellular organisms. Studying the cell as the most important structural unit of living things, cytology occupies a central position in a number of biological disciplines; it is closely related to histology, plant anatomy, physiology, genetics, biochemistry, microbiology, etc. The study of the cellular structure of organisms was begun by microscopists in the 17th century. (R. Hooke, M. Malpighi, A. Leeuwenhoek); in the 19th century a cell theory unified for the entire organic world was created (T. Schwann, 1839). In the 20th century The rapid progress of cytology was facilitated by new methods (electron microscopy, isotope indicators, cell cultivation, etc.).

As a result of the work of many researchers, modern cell theory was created.

The cell is the basic unit of structure, functioning and development of all living organisms;

The cells of all unicellular and multicellular organisms are similar (homologous) in their structure, chemical composition, basic manifestations of life activity and metabolism;

Cell reproduction occurs through cell division; each new cell is formed as a result of the division of the original (mother) cell;

In complex multicellular organisms, cells are specialized in the functions they perform and form tissues; tissues consist of organs that are closely interconnected and subject to nervous and humoral regulation.

Cell theory is one of the most important generalizations of modern biology.

All living things on Earth, with the exception of viruses, are built from cells.

A cell is an elementary integral living system. It should be noted that an animal cell and a plant cell are not identical in structure.

A plant cell has plastids, a membrane (which gives strength and shape to the cell), and vacuoles with cell sap.

Cells, despite their small size, are very complex. Research carried out over many decades makes it possible to reproduce a fairly complete picture of the structure of the cell.

The cell membrane is an ultramicroscopic film consisting of two monomolecular layers of protein and a bimolecular layer of lipids located between them.

Functions of the cell plasma membrane:

Barrier,

Communication with the environment (transport of substances),

Communication between tissue cells in multicellular organisms,

protective.

Cytoplasm is the semi-liquid environment of the cell in which the cell organelles are located. The cytoplasm consists of water and proteins. It is capable of moving at speeds of up to 7 cm/hour.

The movement of cytoplasm within a cell is called cyclosis. There are circular and reticulate cyclosis.

Organelles are secreted into the cell. Organelles are permanent cellular structures, each of which performs its own functions. Among them are:

Cytoplasmic matrix,

Endoplasmic reticulum,

Cell center,

Ribosomes,

Golgi apparatus,

Mitochondria,

plastids,

Lysosomes,

1. Cytoplasmic matrix.

The cytoplasmic matrix is ​​the main and most important part of the cell, its true internal environment.

The components of the cytoplasmic matrix carry out biosynthetic processes in the cell and contain enzymes necessary for energy production.

2. Endoplasmic reticulum.

The entire internal zone of the cytoplasm is filled with numerous small channels and cavities, the walls of which are membranes similar in structure to the plasma membrane. These channels branch, connect with each other and form a network called the endoplasmic reticulum. ES is heterogeneous in its structure. There are two known types of it - granular and smooth.

3. Cell nucleus.

The cell nucleus is the most important part of the cell. It is found in almost all cells of multicellular organisms. Cells of organisms that contain a nucleus are called eukaryotes. The cell nucleus contains DNA, the substance of heredity, in which all the properties of the cell are encrypted.

The structure of the nucleus is divided into: nuclear envelope, nucleoplasm, nucleolus, chromatin.

The cell nucleus performs 2 functions: storing hereditary information and regulating metabolism in the cell.

4. Chromosomes

A chromosome consists of two chromatids and after nuclear division it becomes single chromatid. By the beginning of the next division, a second chromatid is completed on each chromosome. Chromosomes have a primary constriction on which the centromere is located; the constriction divides the chromosome into two arms of equal or different lengths.

Chromatin structures are carriers of DNA. DNA consists of sections - genes that carry hereditary information and are transmitted from ancestors to descendants through germ cells. DNA and RNA are synthesized in chromosomes, which serves as a necessary factor in the transmission of hereditary information during cell division and the construction of protein molecules.

4. Cellular center.

The cell center consists of two centrioles (daughter, mother). Each has a cylindrical shape, the walls are formed by nine triplets of tubes, and in the middle there is a homogeneous substance. The centrioles are located perpendicular to each other. The function of the cell center is to participate in the division of cells of animals and lower plants.

5. Ribosomes

Ribosomes are ultramicroscopic organelles of a round or mushroom shape, consisting of two parts - subparticles. They do not have a membrane structure and consist of protein and RNA. Subparticles are formed in the nucleolus. \

Ribosomes are universal organelles of all animal and plant cells. Found in the cytoplasm in a free state or on the membranes of the endoplasmic reticulum; in addition, they are found in mitochondria and chloroplasts.

6. Mitochondria

Mitochondria are microscopic organelles with a double-membrane structure. The outer membrane is smooth, the inner one forms outgrowths of various shapes - cristae. The mitochondrial matrix (a semi-liquid substance) contains enzymes, ribosomes, DNA, and RNA. The number of mitochondria in one cell ranges from a few to several thousand.

7. Golgi apparatus.

In the cells of plants and protozoa, the Golgi apparatus is represented by individual sickle- or rod-shaped bodies. The Golgi apparatus includes: cavities bounded by membranes and located in groups (5-10), as well as large and small vesicles located at the ends of the cavities. All these elements form a single complex.

Functions: 1) accumulation and transport of substances, chemical modernization,

2) formation of lysosomes,

3) synthesis of lipids and carbohydrates on membrane walls.

8. Plastids.

Plastids are the energy stations of the plant cell. They can change from one species to another. There are several types of plastids: chloroplasts, chromoplasts, leucoplasts.

9. Lysosomes.

Lysosomes are microscopic, single-membrane, round-shaped organelles. Their number depends on the vital activity of the cell and its physiological state. A lysosome is a digestive vacuole containing dissolving enzymes. In case of starvation, the cells digest some organelles.

If the lysosome membrane is destroyed, the cell digests itself.

Animal and plant cells are nourished differently.

Large molecules of proteins and polysaccharides penetrate the cell by phagocytosis (from the Greek phagos - devouring and kitos - vessel, cell), and drops of liquid - by pinocytosis (from the Greek pinot - drink and kitos).

Phagocytosis is a method of feeding animal cells in which nutrients enter the cell.

Pinocytosis is a universal method of nutrition (for both animal and plant cells), in which nutrients enter the cell in dissolved form.

A microscopic cell contains several thousand substances that participate in a variety of chemical reactions. Chemical processes occurring in a cell are one of the main conditions for its life, development and functioning. All cells of animal and plant organisms, as well as microorganisms, are similar in chemical composition, which indicates the unity of the organic world.

Of the 109 elements of Mendeleev's periodic table, a significant majority were found in cells. The cell contains both macroelements and microelements.

In conclusion, we will draw the main conclusions:

A cell is an elementary unit of life, the basis of the structure, life activity, reproduction and individual development of all organisms. There is no life outside the cell (with the exception of viruses).

Most cells are structured the same way: covered with an outer shell - the cell membrane and filled with liquid - cytoplasm. The cytoplasm contains diverse structures - organelles (nucleus, mitochondria, lysosomes, etc.) that carry out various processes.

A cell comes only from a cell.

Each cell performs its own function and interacts with other cells, ensuring the vital functions of the body.

There are no special elements in the cell that are characteristic only of living nature. This indicates the connection and unity of living and inanimate nature.

30. Penetration of nutrients into the cell. The concept of turgor, plasmolysis, plasmoptosis of microorganisms.

Power mechanism. The entry of nutrients into a bacterial cell is a complex physicochemical process, which is facilitated by a number of factors: the difference in the concentration of substances, the size of molecules, their solubility in water or lipids, the pH of the environment, the permeability of cell membranes, etc. In the penetration of nutrients into the cell distinguishes between four possible mechanisms.

The simplest method is passive diffusion, in which the entry of a substance into the cell occurs due to a difference in the concentration gradient (differences in concentration on both sides of the cytoplasmic membrane). The size of the molecule is decisive. Obviously, there are areas in the membrane through which penetration of small substances is possible. One such compound is water.

Most nutrients enter the bacterial cell against a concentration gradient, so this process must involve enzymes and can consume energy. One of these mechanisms is facilitated diffusion, which occurs when the concentration of a substance is higher outside the cell than inside. Facilitated diffusion is a specific process and is carried out by special membrane proteins, carriers, called permease, since they perform the function of enzymes and have specificity. They bind a molecule of the substance, transport it unchanged to the inner surface of the cytoplasmic membrane and release it into the cytoplasm. Since the movement of a substance occurs from a higher concentration to a lower one, this process occurs without the expenditure of energy.

The third possible mechanism for the transport of substances is called active transport. This press is observed at low concentrations of the substrate in the environment and the transport of solutes, also unchanged, occurs against the concentration gradient. Permeases participate in the active transfer of substances. Since the concentration of a substance in a cell can be several thousand times higher than in the external environment, active transfer is necessarily accompanied by the expenditure of energy. Adenosine triphosphate (ATP), accumulated by the bacterial cell during redox processes, is consumed.

And finally, with the fourth possible mechanism of nutrient transfer, translocation of radicals is observed - active transfer of chemically altered molecules that, as a whole, are not able to pass through the membrane. Permeases are involved in the transport of radicals.

The release of substances from the bacterial cell occurs either in the form of passive diffusion (for example, water), or in the process of facilitated diffusion with the participation of permeases.

Organic matter is needed to feed soil microorganisms. There are two ways for organic matter to enter the soil - root excretions of plants with post-harvest residues and the introduction of organic matter into the soil from the outside, in the form of compost, manure, green manure, etc.

Turgor(from Late Latin turgor swelling, filling), internal hydrostatic pressure in a living cell, causing tension in the cell membrane. In animals, cell turgor is usually low; in plant cells, turgor pressure maintains leaves and stems (in herbaceous plants) in an upright position, giving plants strength and stability. Turgor is an indicator of water content and the state of the water regime of plants. A decrease in turgor is accompanied by the processes of autolysis, withering and aging of cells.

If the cell is in a hypertonic solution, the concentration of which is greater than the concentration of the cell sap, then the rate of diffusion of water from the cell sap will exceed the rate of diffusion of water into the cell from the surrounding solution. Due to the release of water from the cell, the volume of cell sap is reduced and turgor decreases. A decrease in the volume of the cell vacuole is accompanied by the separation of the cytoplasm from the membrane - plasmolysis occurs.

Plasmolysis(from the Greek plasmas molded, shaped and... lysed), in biology, the separation of a protoplast from the membrane under the influence of a hypertonic solution on the cell. Plasmolysis is characteristic mainly of plant cells that have a strong cellulose membrane. Animal cells in a hypertonic solution shrink.

Plazmoptiz(plasmo- + Greek ptisis fragmentation) - swelling of microbial

cells and destruction of their membranes in a hypotonic solution.

45. Antibiotics and inhibitory substances. Routes of entry and their influence on the quality of milk. Measures to prevent them from getting into milk.

Antibiotics are a product of the vital activity of various microorganisms. Antibiotics have an inhibitory effect on the proliferation of other microbes and are therefore used to treat various infectious diseases. A group of antibiotics that block the synthesis of nucleic acids (DNA and RNA) is used as immunosuppressants, since in parallel with the inhibition of bacterial growth, it inhibits the proliferation (reproduction) of cells of the immune system. Representatives of this group of drugs are Actinomycin

Particular attention should be paid to measures to prevent the entry of antibiotics into animal products. Antibiotics can get into milk when treating animals, as well as when feeding lactating cows concentrated and other feed intended for pigs, or biological waste containing mycelium and other antibiotics. Apparently, the possibility of deliberately adding antibiotics to milk in order to reduce bacterial contamination of collected milk cannot be completely ruled out.

Several methods are used to identify inhibitory substances in milk. The simplest, most accessible and less labor-intensive is biological. The essence of the method is to suppress the growth of lactic acid streptococcus, sensitive to inhibitory substances, for example Str. thermo-philus added to the test milk sample containing an inhibitory substance. The result of the reaction is recorded by the color of the milk column into which the indicator is added. The initial color indicates a positive reaction, i.e., the presence of an inhibitory substance. However, milk contains so-called natural inhibitory substances, such as lactoferrin, properdin, lysozymes and many others, which also inhibit the growth of lactic acid bacteria and in particular Str. thermophilus. Therefore, although it is expected that most natural inhibitory substances should be destroyed when the sample is heated for 10 minutes at 85°C, the biological method is not specific and additional research is required to determine the type of chemical or antibiotic added. For this reason, to date there is no single biological method with which it would be possible to identify inhibitory substances in

The problem of milk contamination with inhibitory substances, including antibiotics, is becoming increasingly important every year.

Inhibiting substances include antibiotics, sulfonamides, nitrofurans, nitrates, preservatives (formalin, hydrogen peroxide), neutralizing agents (soda, sodium hydroxide, ammonia), detergents and disinfectants, etc.

The presence of antibiotic residues is a particular danger to humans and a serious problem for the dairy industry, since they can disrupt the production process by inhibiting starter microflora. This leads to serious financial losses. But the most dangerous consequences are the ingestion of antibiotic residues into the human body.

Pesticides used to protect plants from pests also pose a risk to human and animal health. Milk containing residual quantities is not accepted for processing. Pesticides differ in their specific action. Chlorine-containing insecticides are persistent and lipolytic, making their presence particularly hazardous in foods. Organic phosphate esters and carbamates do not accumulate in food products and are not of interest for milk hygiene. Herbicides and fungicides are generally not very stable. Their residues in milk have not yet been detected, so it is not practical to determine their content.

The manifestation of the inhibitory properties of milk is influenced by a variety of factors. Possible sources of inhibitors getting into milk are: violations in the rejection of milk during the treatment of animals; sanitary treatment of milking and dairy equipment; use of low-quality feed; ingestion of a number of chemicals with food.

The inhibitory properties of milk can be influenced by cow feeding and feed quality. The dosage of chemical reagents when canning silage should be strictly observed. The inhibitory properties of milk may be influenced by the presence of increased levels of nitrates or nitrites in feed.

In order to prevent residual amounts of detergents, detergents-disinfectants and disinfectants from entering milk and their possible influence on the results of determining inhibitory substances, sanitary treatment of milking and dairy equipment must be carried out strictly in accordance with sanitary rules. In case of positive reactions to the presence of residual amounts of sanitary products on the surface of milking and dairy equipment

it is necessary to rinse it again with water.

One of the ways that antibiotics and other drugs get into milk is through their intramuscular administration. The presence of antibiotics and sulfonamides is most often observed when cows are treated for mastitis.

Taking into account the specific effects of various inhibitory substances on both human and animal health and the technological properties of milk, the solution to the problem under consideration largely depends on the development and implementation of highly effective, highly specific methods for monitoring the presence of inhibitory substances. It is not enough to establish their presence; it is important to determine not only the type, but also the specific substance that caused the manifestation of the inhibitory properties of milk. This allows you to analyze the situation in order to determine the possible source of entry of this substance into it.

Currently, the country has GOST standards for methods for determining inhibitory substances in milk. In particular, at dairy enterprises it is possible to determine the presence of soda, ammonia, and hydrogen peroxide in it.

Another important condition for ensuring the safety of milk, including its inhibitory properties, is quality control exclusively in independent testing laboratories. In this regard, there is an urgent need to create a state regulatory framework, including a system of payments for raw milk between rural producers and purchasing factories based on measurements of milk quality by such laboratories.

50. Microflora of plants and feed.

Epiphytic microflora.

A variety of microflora, called epiphytic, are constantly present on the surface parts of plants. The following non-spore species of microorganisms are most often found on stems, leaves, flowers, and fruits: Bact, herbicola makes up 40% of the total epiphytic microflora, Ps. fluorescens - 40%, lactic acid bacteria - 10%, similar bacteria - 2%, yeast, mold fungi, cellulose, butyric acid, thermophilic bacteria -

After mowing and loss of plant resistance, as well as due to mechanical damage to their tissues, epiphytic and, above all, putrefactive microflora, intensively multiplying, penetrates the thickness of plant tissues and causes their decomposition. That is why crop products (grain, roughage and succulent feed) are protected from the destructive effects of epiphytic microflora by various preservation methods.

It is known that plants have bound water, which is part of their chemical substances, and free water - droplet-liquid. Microorganisms can reproduce in plant matter only if there is free water in it. One of the most common and accessible methods for removing free water from crop products and, therefore, preserving them is drying and ensiling.

Drying grain and hay involves removing free water from them. Therefore, microorganisms cannot multiply on them as long as these products are dry.

Freshly cut, unseasoned grass contains 70-80% water, dried hay only 12-16%, the remaining moisture is bound to organic substances and is not used by microorganisms. During drying of hay, about 10% of organic matter is lost, mainly during the decomposition of proteins and sugars. Particularly large losses of nutrients, vitamins and mineral compounds occur in dried hay located in swaths (windrows) when it often rains. Rain distilled water washes them out up to 50%. Significant losses of dry matter occur in the grain during self-heating. This process is caused by thermogenesis, that is, the creation of heat by microorganisms. It arises because thermophilic bacteria use for their life only 5 - 10% of the energy of the nutrients they consume, and the rest is released into their environment - grain, hay.

Feed silage. When growing feed crops (corn, sorghum, etc.) per hectare, it is possible to obtain significantly more feed units in green mass than in grain. In terms of starch equivalent, the nutritional value of green mass during drying can decrease to 50%, and during ensiling only up to 20%. When ensiling, small leaves of plants with high nutritional value are not lost, but when dried, they fall off. Silage laying can also be done in variable weather. Good silage is a juicy, vitamin-rich, milk-rich feed.

The essence of ensiling is that in the crushed green mass stored in a container, lactic acid microbes intensively multiply, decomposing sugars with the formation of lactic acid, which accumulates up to 1.5-2.5% of the silage weight. At the same time, acetic acid bacteria multiply, converting alcohol and other carbohydrates into acetic acid; it accumulates 0.4-0.6% of the silage weight. Lactic and acetic acids are strong poisons for putrefactive microbes, so their reproduction stops.

Silage remains in good condition for up to three years as long as it contains at least 2% lactic and acetic acids and a pH of 4-4.2. If the proliferation of lactic acid and acetic bacteria weakens, the concentration of acids decreases. At this time, yeast, mold, butyric acid and putrefactive bacteria begin to multiply at the same time and the silage deteriorates. Thus, obtaining good silage depends primarily on the presence of sucrose in the green mass and the intensity of development of lactic acid bacteria.

In the process of silage maturation, three microbiological phases are distinguished, characterized by a specific species composition of microflora.

The first phase is characterized by the proliferation of mixed microflora with some predominance of putrefactive aerobic non-spore bacteria - Escherichia coli, Pseudomonas, lactic acid microbes, yeast. Spore-bearing putrefactive and butyric acid bacteria multiply slowly and do not predominate over lactic acid bacteria. The main medium for the development of mixed microflora at this stage is plant sap, released from plant tissues and filling the space between the crushed plant mass. This helps create anaerobic conditions in the silage, which inhibits the development of putrefactive bacteria and favors the proliferation of lactic acid microbes. The first phase when silage is densely laid, that is, under anaerobic conditions, lasts only 1-3 days; when silage is loosely laid under aerobic conditions, it is longer and lasts 1-2 weeks. During this time, the silage is heated due to intense aerobic microbiological processes. The second phase of silage maturation is characterized by rapid proliferation of lactic acid microbes, with predominantly coccal forms developing initially, which are then replaced by lactic acid bacteria.

Thanks to the accumulation of lactic acid, the development of all putrefactive and butyric acid microorganisms stops, while their vegetative forms die, leaving only spore-bearing ones (in the form of spores). With full compliance with the silage laying technology, homofermentative lactic acid bacteria multiply in this phase, producing only lactic acid from sugars. If the technology for laying silos is violated, when in it. air is contained, the microflora of heterofermentative fermentation develops, resulting in the formation of undesirable volatile acids - butyric, acetic, etc. The duration of the second phase is from two weeks to three months.

The third phase is characterized by the gradual death of lactic acid microbes in the silage due to the high concentration of lactic acid (2.5%). At this time, the ripening of the silage is completed; the acidity of the silage mass, which decreases to pH 4.2 - 4.5, is considered a conditional indicator of its suitability for feeding (Fig. 37). Under aerobic conditions, molds and yeasts begin to multiply, which break down lactic acid, butyric acid and putrefactive bacteria sprouting from spores take advantage of this, as a result the silage becomes moldy and rots.

Defects of silage of microbial origin. If proper conditions for laying and storing silage are not observed, certain defects arise in it.

Rotting of silage, accompanied by significant self-heating, is noted when it is laid loosely and insufficiently compacted. The rapid development of putrefactive and thermophilic microbes is facilitated by the air in the silo. As a result of protein decomposition, silage acquires a putrid, ammonia-like odor and becomes unusable.

acquires a putrid, ammonia-like odor even when fed. Rotting of silage occurs in the first microbiological phase, when the development of lactic acid microbes and the accumulation of lactic acid, which suppresses putrefactive bacteria, are delayed. To stop the development of the latter, it is necessary to reduce the pH in the silage to 4.2-4.5. Silage rotting is caused by Er. herbicola, E. coli, Ps. aerogenes. P. vulgaris, B. subtilis, Ps. fluorescens, as well as molds.

Rancidity of silage is caused by the accumulation of butyric acid, which has a sharp bitter taste and unpleasant odor. In good silage there is no butyric acid, in silage of average quality it is found up to 0.2%, and in silage unsuitable for feeding - up to 1%.

The causative agents of butyric acid fermentation are capable of converting lactic acid into butyric acid, as well as causing putrefactive decomposition of proteins, which aggravates their negative effect on the quality of silage. Butyric acid fermentation occurs with the slow development of lactic acid bacteria and insufficient accumulation of lactic acid, at a pH above 4.7. With the rapid accumulation of lactic acid in the silage to 2% and a pH of 4-4.2, butyric acid fermentation does not occur.

The main causative agents of butyric acid fermentation in silage: Ps. fluo-rescens, Cl. pasteurianum, Cl. felsineum.

Peroxidation of silage occurs when acetic acid bacteria, as well as putrefactive bacteria capable of producing acetic acid, actively multiply in it. Acetic acid bacteria multiply especially intensively in the presence of ethyl alcohol in the silage, accumulated by alcoholic fermentation yeast. Yeast and acetic acid bacteria are aerobes, therefore a significant content of acetic acid in the silage and, consequently, its peroxidation is noted when there is air in the silage.

Silage molding occurs when there is air in the silo, which favors the intensive development of molds and yeasts. These microorganisms are always found on plants, so under favorable conditions they begin to multiply rapidly.

Rhizosphere and epiphytic microflora can also play a negative role. Root crops are often affected by rot (black – Alternaria radicina, gray – Botrutus cinirea, potato – Phitophtora infenstans). Damage to silage is caused by excessive activity of butyric acid fermentation agents. Ergot (claviceps purpurae), which causes the disease ergotism, multiplies on vegetative plants. Fungi cause toxicosis. The causative agent of botulism (Cl. botulinum), getting into the feed with soil and feces, causes severe toxicosis, often fatal. Many fungi (Aspergillus, Penicillum, Mucor, Fusarium, Stachybotrus) colonize food, multiplying under favorable conditions, and cause acute or chronic toxicosis in animals, often accompanied by nonspecific symptoms.

Microbiological preparations are used in the diets of animals and birds. Enzymes improve feed absorption. Vitamins and amino acids are obtained on a microbiological basis. It is possible to use bacterial protein. Feeder's yeast is a good protein and vitamin feed. Yeast contains easily digestible protein, provitamin D (zrgosterol), as well as vitamins A, B, E. Yeast multiplies very quickly, so in industrial conditions it is possible to obtain a large amount of yeast mass when cultivating it on molasses or saccharified fiber. Currently, in our country, dry feed yeast is prepared in large quantities. For their production, a culture of feed yeast is used.

66. Characterize the causative agents of tuberculosis and brucellosis.

Brucellosis – a disease that affects not only cattle, but also pigs, rats and other animals. The causative agents are bacteria of the genus Brucella. These are small, non-motile coccoid bacteria, gram-negative, do not form spores, aerobes. Contains endotoxin. The extreme limits of growth are 6-450C, the optimum temperature is 370C. When heated to 60-650C, these bacteria die in 20-30 minutes; when boiled, in a few seconds. Brucella is characterized by high viability: in dairy products (cheese, cheese, butter) they persist for several months. The incubation period is 1-3 weeks or more. Milk from foci of this infection is pasteurized at elevated temperatures (at 700 C for 30 minutes), boiled for 5 minutes or sterilized.

Brucellosis - chronic animal disease. It is detected in milk by a ring test based on the detection of appropriate antibodies. In farms that are unfavorable for brucellosis, it is prohibited to export milk from a herd that is recovering in a non-disinfected

form. Such milk is pasteurized and either transported to the dairy plant or used on the farm. Milk from cows that react positively to

brucellosis, boiled and used for on-farm needs.

Tuberculosis – caused by mycobacteria of the genus Mycobacterium, which belong to the actinomycetes. The shape of the cells is variable: rods are straight, branched and curved. Aerobes are immobile and do not form spores, but due to the high content of mycolic acid and lipids, they are resistant to acids, alkalis, alcohol, drying, and heating. They are stored in dairy products for a long time (in cheese – 2 months, in butter – up to 3 months). Sensitive to sunlight, ultraviolet rays, high temperature: at 700C they die after 10 minutes, at 1000C - after 10 seconds. Tuberculosis is distinguished from other infections by a long incubation period - from several weeks to several years. In order to prevent this infection, it is not allowed to use milk from sick animals for food.

Tuberculosis – chronic disease of animals. Excreted with milk,

Mycobacterium tuberculosis, which has a waxy coating, can survive for a long time

stored in the external environment. Milk from a farm unaffected by tuberculosis is pasteurized directly on the farm at a temperature of 85 0C for 30 minutes.

or at a temperature of 90 0C for 5 minutes. Disinfected in this way-

Bom milk obtained from animals of health groups is sent to

is sent to a dairy plant, where it is re-pasteurized and accepted as a second

variety. Milk from animals that react positively to tuberculin

disinfected by boiling, after which they are used for fattening young

Nyaka. Milk obtained from animals with clinical signs of tuberculosis

berculosis, used in the diet of fattening animals after 10

minute boiling. Milk is destroyed due to udder tuberculosis.

The widespread introduction of physical research methods into biology has made it possible to study biological phenomena at the molecular level. The brilliant work of biochemists, physiologists, biophysicists and crystallographers has established the molecular structures of a number of important biological objects. For example, the structure of deoxyribonucleic acid (DNA) - the main carrier of hereditary information, the structure of myoglobin molecules that store oxygen in the muscles of animals, the structure of hemoglobin molecules that are part of red blood cells and carry oxygen from the lungs to tissues, the structure of striated muscles and protein molecules, their constituents, the structure of some enzymes, vitamins and a number of other important biological molecules.

New experimental data obtained from the study of biological processes at the molecular level have put the question of their interpretation on the agenda. Since all living organisms are built from molecules and atoms, elucidation at the molecular level of the mechanism of bioprocesses is possible only with the help of quantum theory, which successfully describes the movement of electrons and nuclei that make up molecules and atoms.

The close connection between biology and physics appeared already in the early stages of the development of natural science. However, along with the materialistic understanding of the connection between physics and biology, for a long time there was a deeply erroneous, anti-scientific point of view, called “vitalism”. The vitalists argued that the living was allegedly separated from the non-living by an impassable abyss and was subject not to natural laws, but to “vital force” and therefore incomprehensible to humans.

The views of the vitalists have long been rejected by science. Currently, no one doubts that life is special

manifestation of physical and chemical processes occurring in complex molecular systems that interact with other systems through the exchange of energy and matter. However, even now some scientists are of the opinion that the complexity of biological systems excludes the possibility of their interpretation at the molecular level.

It should, of course, be borne in mind that biological objects have a number of very unique features that distinguish them from bodies of inanimate nature. These features primarily include self-reproduction and adaptation to changing external conditions, the finest regulation and self-consistency of all biological processes occurring in living systems and ensuring their vital activity.

The molecules that make up living organisms are unusually large, diverse and complex. The most complex and diverse of all the molecules that make up cells are protein molecules. Their molecular weights vary from several tens of thousands to several millions.

The greatest diversity of biological organisms does not mean the extreme diversity of the chemical units from which they are built. This diversity is determined by numerous combinations of the same compounds and atomic groups. For example, all proteins consist primarily of 20 amino acid residues. DNA molecules are built from four types of nucleotides.

When studying inanimate bodies, it was found that as atomic systems become more complex, new qualities appear. The concepts of temperature, entropy, sound waves and other elementary collective excitations are applicable to a system of atoms and molecules, but are not applicable to a single atom.

There can be no doubt that all the uniqueness of living organisms, which distinguishes them from bodies of inanimate nature, arises as a result of the special organization of complex molecular systems, which are based on the same elementary laws that determine the properties of atoms and molecules and inanimate bodies built from them nature.

The growth, development and reproduction of living organisms are associated with a variety of chemical reactions. Biochemistry has made a significant contribution to their study. However, in biochemistry, the main attention was paid to the study of the interaction between atoms in direct contact. As Nobel laureate Szent-Gyorgyi wrote in 1957

Let's try to consider several lesson topics that are related to biology, literature, geography, art, and music.

1. Lesson in 6th grade on the topic: “Composition of seeds of monocots and dicotyledons”

Purpose of the lesson: to study the chemical composition of seeds of monocotyledonous and dicotyledonous plants.

Tasks:

a) general education:

• give an idea of ​​the need for mineral and organic substances for the formation and growth of a plant;
• repeat the structural features of seeds of monocotyledonous and dicotyledonous plants;
• deepen and expand knowledge of the material about the chemical composition of the cell;
• test knowledge of biological terminology;

b) developing:

Develop the ability to work with natural objects and compare them;

• develop the ability to work with a textbook;
• be able to apply acquired knowledge in practice;
• instill the skills of independent work with additional literature;
• promote the development of will and perseverance in learning;
• develop the ability to generalize and draw conclusions;
• develop logical thinking, cognitive interest in the subject;

c) educational:

• continue the formation of a scientific worldview;
• teach methods of active communication during collective discussion and decision-making;
• Carry out environmental and environmental education using the lesson material as an example;
• cultivate a culture of communication.

You can start learning new material with riddles:

1. In a small hut, in a bedroom, a small child is sleeping,
There is food in the pantry, when you wake up you will be full.

(seed with embryo and nutrients)

2. The flower is a lionfish, and the fruit is a scapula
The fruit is green and young. But sweet like malt.

(peas)

3. Even on the day of mowing, the bush is lower than the millet,
But one seed is equal to a hundred straws

(beans)

4. Of the plants whose portrait is stamped on the coin?
Whose fruits are more needed on the earth’s planet?

(wheat)

When conducting laboratory work, finding out the chemical composition of seeds, during a conversation about mineral salts and water, it is appropriate to talk about soil protection: soil is accessible to plant roots only in the form of solutions, so it is important to preserve moisture in the soil.

“... Stop! Come to your senses!

The forests whisper to man.

Don't expose the ground.

Don't turn it into a desert.

Have mercy! - echoes the earth.

You cut down trees, it deprives me of moisture.

I’m drying up... Soon I won’t be able to give birth to anything: neither a grain nor a flower.”

2. A biology lesson in the 6th grade on the topic: “Fertilization and pollination in angiosperms” is accompanied by music by N. A. Rimsky - Korsakov - “The Flight of the Bumblebee” from the opera “The Tale of Tsar Saltan.”

Nature's sweet creation,

Flower, valley decoration,

For a moment cherished in spring,

You are unknown and deaf in the steppe!

Tell me: why are you so red,

Sparkling with dew, you flame

And you breathe something as if alive,

Fragrant and holy?

For whom are you in the wide steppe,

For whom are you far from the villages?...

(Alexey Koltsov)

Interdisciplinary connections in the lesson:

Geography - distribution of plants on different continents

Ecology – protection of flowering plants

Music – listening to music

Literature – poems about flowers

3. Biology lesson in 7th grade on the topic: “Class Bony fish.”

While updating your knowledge, you can read an excerpt from a poem by F.I. Tyutchev

“Others got it from nature

Instinct prophetically - blind -

They smell it, hear the water"

Excerpts from fairy tales by A.S. are used. Pushkin about Tsar Saltan,about the Goldfish, poem by Valentin Berestov “Why does the frog have no tail”,Krylov’s fable “Demyanov’s Ear”, paintings by Viktor Matorin “Five Loaves and Two Fishes”, “Seven Loaves”, V. Perov “Fisherman”, painting by Henri Matisse “Red Fishes”.

During the lesson, music from the movie “Amphibian Man” is played,And Camille Saint - Sansa musical work “Carnival of Animals” - study “Aquarium”.

4. Biology lesson in 8th grade on the topic: “Structure and work of the heart”

New material begins with a poemEduardas Mezhelaitis “What is the heart?”
What is a heart? Is the stone hard?
An apple with purple-red skin?
Maybe between the ribs and the aorta
Is there a beating ball that looks like a globe on Earth?
One way or another, everything earthly
Fits within its boundaries
Because he has no peace
He cares about everything.

Many works are dedicated to the “heart”, for example: M. Gorky - “Old Woman Izergil”, which talks about the brave heart of Danko, Wilhem Hauff - “Frozen Heart”, Bulgakov “Heart of a Dog”.

Not only writers and poets, but also musicians dedicated their works to the “heart.” Music can not only lift your spirits, invigorate or calm you down, it can treat serious illnesses. For example,

Mendelssohn's Wedding March, Chopin's Nocturne in D Minor and Bach's Violin Concerto in D Minor will normalize the cardiovascular system.

As a sign of loyalty and love for the amazing organ of the human heart, a monument was erected. A huge heart made of red granite weighing four tons - a symbol of life - decorates the courtyard of the Heart Institute in Perm. The opening of Russia's first monument to the human heart took place on June 12, 2001. The granite sculpture is an anatomically accurate copy of the main human organ.

Thus, interdisciplinary is a modern teaching principle that influences the selection and structure of educational material for a number of subjects, strengthening the systematic knowledge of students, activates teaching methods, orients towards the use of complex forms of educational organization, ensuring the unity of the educational process. And the implementation of interdisciplinary connections is an important means of increasing the effectiveness of schoolchildren’s cognitive activity, since a deep and versatile disclosure of the content of all academic subjects in interconnection and interdependence contributes to:

1. More stable systemic assimilation of educational information;

2.Formation in students’ abilities to quickly use knowledge of various disciplines in mastering new knowledge;

3. Development of key competencies among students.

4. Wide application of acquired knowledge in practice.

5.Preparation for the final certification.

CONCLUSION

Interdisciplinary connections in teaching biology are considered as a didactic principle and as a condition, capturing the goals and objectives, content, methods, means and forms of teaching various academic subjects.

Interdisciplinary connections make it possible to isolate the main elements of the content of education, to provide for the development of system-forming ideas, concepts, general scientific methods of educational activity, and the possibility of comprehensive application of knowledge from various subjects in the work activities of students.

Interdisciplinary connections influence the composition and structure of academic subjects. Each academic subject is a source of certain types of interdisciplinary connections. Therefore, it is possible to identify those connections that are taken into account in the content of biology, and, conversely, those going from biology to other academic subjects.

The formation of a general system of students' knowledge about the real world, reflecting the interrelations of various forms of matter movement, is one of the main educational functions of interdisciplinary connections. The formation of an integral scientific worldview requires mandatory consideration of interdisciplinary connections. An integrated approach to education has strengthened the educational functions of interdisciplinary connections in the biology course, thereby promoting the revelation of the unity of the nature of society - man.

Under these conditions, the connections of biology with both natural science and humanities subjects are strengthened; skills in transferring knowledge, their application and comprehensive understanding are improved.

Thus, interdisciplinary is a modern teaching principle that influences the selection and structure of educational material for a number of subjects, strengthening the systematic knowledge of students, activates teaching methods, orients towards the use of complex forms of educational organization, ensuring the unity of the educational process.

LITERATURE

1. Vsesvyatsky B.V. Systematic approach to biological education in secondary school. - M.: Education, 1985.

2. Zverev I. D., Myagkova A. N. General methods of teaching biology. - M.: Education, 1985.

3. Ilchenko V. R. Crossroads of physics, chemistry and biology. - M.: Education, 1986.

4. Maksimova V. N., Gruzdeva N. V. Interdisciplinary connections in teaching biology. - M.: Education, 1987.

5. Maksimova V. N. Interdisciplinary connections in the educational process of modern school. -M.: Education, 1986.

All theoretical and practical medical sciences use general biological patterns.

Question 2. Methods of biological sciences

Basic methods of biology

Main private methods in biology are:

Descriptive,

Comparative,

Historical,

Experimental.

In order to find out the essence of phenomena, it is necessary first of all to collect factual material and describe it. Collecting and describing facts was the main method of research in early period of development of biology, which, however, has not lost its significance to this day.

Back in the 18th century. became widespread comparative method, allowing, through comparison, to study the similarities and differences of organisms and their parts. Systematics was based on the principles of this method and one of the largest generalizations was made - the cell theory was created. The comparative method has developed into historical, but has not lost its significance even now.

Historical method

Historical method clarifies the patterns of the appearance and development of organisms, the formation of their structure and functions. Science is obliged to establish the historical method in biology C. Darwin.

Experimental method

The experimental method of studying natural phenomena is associated with active influence on them by setting up experiments (experiments) under precisely taken into account conditions and by changing the flow of processes in the direction desired by the researcher. This method allows you to study phenomena in isolation and achieve their repeatability when reproducing the same conditions. The experiment provides not only deeper insight into the essence of phenomena than other methods, but also direct mastery of them.

The highest form of experiment is modeling of the processes being studied. A brilliant experimenter I.P. Pavlov said: “Observation collects what nature offers it, but experience takes from nature what it wants.”

The integrated use of various methods allows us to more fully understand the phenomena and objects of nature. The current rapprochement between biology and chemistry, physics, mathematics and cybernetics, and the use of their methods to solve biological problems have proven to be very fruitful.

Question 3. Stages of development of biology

Evolution of biology

The development of each science is in a known depending on the production method, social system, practical needs, general level of science and technology. Primitive man began to accumulate the first information about living organisms. Living organisms provided him with food, material for clothing and housing. Already at that time, there was a need to know the properties of plants and animals, their places of habitat and growth, the timing of ripening of fruits and seeds, and the behavior of animals. Thus, gradually, not out of idle curiosity, but as a result of pressing everyday needs, information about living organisms accumulated. The domestication of animals and the beginning of plant cultivation required more in-depth knowledge of living organisms.

Initially, accumulated experience was passed on orally from one generation to another. The advent of writing contributed to better preservation and transmission of knowledge.

The information became more complete and richer. However, for a long time, due to the low level of development of social production, biological science did not yet exist.

INTRODUCTION

§ 1.BIOLOGICAL SCIENCES SYSTEM.RELATIONSHIP OF BIOLOGICAL SCIENCES WITH OTHER SCIENCES

Biology is a complex science about living nature. You already know that biology studies different manifestations of life. As an independent natural science, biology originated before our era, and its name was proposed in 1802 independently by the French scientist Jean-Baptiste Lamarck (1744-1829) and the German Gottfried Reinhold Treviranus (1766-1837).

During the previous years of schooling, you have already become familiar with the basics of biological sciences such as botany, mycology, zoology, human anatomy and physiology, etc. Over the next years, you will learn about the achievements of other biological sciences: biochemistry, cytology, virology, biology individual development, genetics, ecology, evolutionary studies, systematics, paleontology and the like. Data from these and many other biological sciences make it possible to study the patterns inherent in all living organisms. Review Figure 1.1 for a summary of the basic biological sciences. (Think about which of the biological sciences in the diagram you think are most related to each other)

Biology is called the leading science of the 21st century. Without the achievements of biology, progress in agricultural sciences, health care and the environment, biotechnology, and the like is currently impossible.

Relationships between biology and other sciences. Biology is closely related to other natural and human sciences. As a result of interaction with chemistry, biochemistry arose, and with physics, biophysics arose. Biogeography - a complex science about the distribution of living organisms on Earth - was developed through the efforts of several generations of scientists who studied flora, fauna, and species groups in different geographical parts of our planet. All branches of biology use mathematical methods for processing collected material.

Rice. 1.1. Brief description of the basic biological sciences

As a result of the interaction of ecology with the humanities, socioecology arose (studies the patterns of interaction between human society and the natural environment), and the interaction of human biology with the humanities formed anthropology - the science of the origin and evolution of man as a special biosocial species, human races, and the like.

Philosophy of biology is a science that arose as a result of the interaction of classical philosophy with biology. She studies problems of worldview in the light of advances in biology.

Data from the biological sciences about humans (anatomy, physiology, human genetics) serve as the theoretical basis for medicine (the science of human health and its preservation, diseases, methods of their diagnosis and treatment).

In the second half of the twentieth century. Thanks to the successes of various natural sciences (physics, mathematics, cybernetics, chemistry and others), new areas of biological research have emerged:

Space biology - studies the peculiarities of the functioning of living systems in the conditions of spacecraft and the Universe;

Bionics - studies the structural features and vital functions of organisms in order to create various technical systems and devices;

Radiobiology is the science of the influence of different types of ionizing radiation on living systems;

Cryobiology is the science of the influence of low temperatures on living matter.

Modern society often faces problems that arise at the intersection with other sciences. For example, to assess the consequences of anthropogenic impacts on living systems (radiation, chemical, etc.), the joint efforts of biologists, doctors, physicists, chemists, etc. are needed. The creation of bioinformation technologies (for example, to study the structure and functions of sets of hereditary information of organisms) is impossible without special computer programs. The study of hereditary human diseases is also a task for many sciences (genetics, biochemistry, medicine and others).

Key terms and concepts. Biology, system of biological sciences.

Kopotko about the main thing

Biology is a complex of sciences that studies various manifestations of life.

The name “biology” was proposed in 1802 by the French scientist J.-By. Lamarck and German - G. G. Treviranus.

Biology has close connections both with other natural sciences and with the humanities. Due to interaction with other sciences,

biochemistry, biophysics, biogeography, radiobiology and many others.

Man, as an integral part of nature, has long sought to study the animals and plants that surrounded her, because her survival depended on it. The first attempts to organize the accumulated data on the structure of animals and plants, their life processes and diversity belonged to the scientists of Ancient Greece - Aristotle (Fig. 1.2) and Theophrastus. Aristotle created the first scientific system for about 500 species of animals known at that time and laid the foundations for comparative anatomy (try to define the objectives of this science). He believed that living matter arose from nonliving matter. Theophrastus (372-287 AD) described various plant organs and laid the foundations for botanical classification. The living nature systems of these two scientists became the basis for the development of European biological science and did not change significantly until the 8th century. n. e.

During the Middle Ages (V - XV centuries AD), biology developed primarily as a descriptive science. The accumulated facts in those days were often distorted. For example, there are descriptions of various mythical creatures, for example, a “sea monk” who seemed to appear to sailors before a storm, or starfish with a human face.

During the Renaissance, the rapid development of industry, agriculture, and outstanding geographical discoveries posed new challenges for science, which stimulated its development. Thus, the development of cytology is associated with the invention of the light microscope. A light microscope with an eyepiece and a lens appeared at the beginning of the 17th century, but its inventor is not exactly known; in particular, the great Italian scientist G. Galileo demonstrated the double-lens magnifying device he had invented back in 1609. And in 1665, using his own improved microscope, studying thin sections of elderberry cork, carrots, etc. Robert Hooke (Fig. 1.3) discovered the cellular structure plant tissues and proposed the term cell itself. Around the same time, the Dutch naturalist Antonie van Leeuwenhoek (Fig. 1.4) produced unique lenses with 150-300x magnification, through which he first observed single-celled organisms (single-celled animals and bacteria), sperm, red blood cells and their movement in capillaries.

All accumulated scientific facts about the diversity of living things were summarized by an outstanding Swedish scientist of the 18th century. Carl Linnaeus (Fig. 1.5). He emphasized that in nature there are groups of individuals that resemble each other in terms of structural features and environmental requirements, populating a certain part of the Earth’s surface, and are capable of interbreeding with each other and producing fertile descendants. He considered such groups, each of which has certain differences from the others, as species. Linnaeus laid the foundation for modern taxonomy and also created his own classification of plants and animals. He introduced Latin scientific names for species, genera and other systematic categories, described more than 7,500 plant species and about 4,000 animal species.

Rice. 1.2. Aristotle (384-322 RR. AD)

Rice. 1.3. Robert Hooke (1635-1703)

Rice. 1.4. Antonie van Leeuwenhoek (1632-1723)

Rice. 1.5. Carl Linnaeus(1707-1778)

Rice. 1.6. Theodor Schwann (1810-1882)

Rice. 1.7. Jean - Baptiste Lamarck (1744-1829)

Rice. 1.8. Charles Darwin (1809-1882)

An important stage in the development of biology is associated with the creation of cell theory and the development of evolutionary ideas. In particular, a nucleus was discovered in a cell: it was first observed in a plant cell in 1828 by the English botanist Robert Brown (1773-1858), who subsequently (1833) proposed the term “nucleus”. In 1830, the nucleus of a chicken egg was described by the Czech researcher Jan Purkine (1787-1869). Based on the works of these scientists and the German botanist Matthias Schleiden (1804-1881), the German zoologist Theodor Schwann (Fig. 1.6) in 1838 formulated the basic principles of the cell theory, subsequently supplemented by the German cytologist Rudolf Virchow (1821-1902).

At the beginning of the 19th century. Jean-Baptiste Lamarck (Fig. 1.7) proposed the first holistic evolutionary hypothesis (1809) and drew attention to the role of environmental factors in the evolution of living beings. The most significant contribution to the subsequent development of evolutionary views was made by one of the most outstanding biologists in the world - the English scientist Charles Darwin (Fig. 1.8). His evolutionary hypothesis (1859) laid the foundation for theoretical biology and significantly influenced the development of other natural sciences. The teachings of Charles Darwin were subsequently supplemented and expanded by the works of his followers, and as a complete system of views called “Darwinism” it was finally formed at the beginning of the twentieth century. The greatest role in the development of Darwinism of that time was played by the famous German scientist Ernst Haeckel (Fig. 1.9), who, in particular, proposed in 1866 the name of the science of the relationship of organisms and their communities with environmental conditions - ecology. He tried to figure out and schematically depict the evolutionary paths of various systematic groups of animals and plants, laying the foundations of phylogeny.

An important contribution to the development of the doctrine of higher nervous activity and the physiology of digestion in vertebrates and humans was made by Russian scientists Ivan Mikhailovich Sechenov and Ivan Petrovich Pavlov (Fig. 1.10, 1.11), which you already know from the 9th grade biology course.

Rice. 1.9. Ernst Haeckel (1834-1919)

Rice. 1.10. I. M. Sechenov (1829-1905)

Rice. 1.11. I. P. Pavlov (1849-1936)

Rice. 1.12. Gregor Mendel (1822-1884)

Rice. 1.13. Thomas Hunt Morgan (1866-1945)

Rice. 1.14. James Watson (1928) (1) and Francis Crick (1916-2004) (2)

In the middle of the 19th century. The foundations of the science of the laws of heredity and variability of organisms - genetics - were laid. The date of her birth is considered to be 1900, when three scientists who conducted experiments on plant hybridization - the Dutchman Hugo de Vries (1848-1935) (he owned the term mutation), the German Karl Erich Correns (1864-1933) and the Austrian Erich Tsermak (1871- 1962) independently came across the forgotten work of the Czech researcher Gregor Mendel (Fig. 1.12) “Experiments on plant hybrids,” published in 1865. These scientists were amazed at how the results of their experiments coincided with those obtained by G. Mendel. Subsequently, the laws of heredity established by G. Mendel were accepted by scientists from different countries, and careful research showed their universal nature. The name “genetics” was proposed in 1907 by the English scientist William Bateson (1861-1926). The American scientist Thomas Hunt Morgan (Fig. 1.13) and his collaborators made a huge contribution to the development of genetics. The result of their research was the creation of the chromosomal theory of heredity, which influenced the further development of not only genetics, but also biology in general. Now genetics is developing rapidly and occupies one of the central places in biology.

At the end of the 19th century. (1892) Russian scientist Dmitry Iosifovich Ivanovsky (1864-1920) discovered non-cellular life forms - viruses. This name was soon proposed by the Dutch researcher Martin Willem Beijerink (1851-1931). However, the development of virology became possible only with the invention of the electron microscope (30s of the 20th century), capable of magnifying research objects tens and hundreds of thousands of times. Thanks to the electron microscope, people were able to study cell membranes, tiny organelles and inclusions in detail.

In the 20th century. molecular biology, genetic engineering, biotechnology, etc. were rapidly developing. The American scientist - biochemist James Watson, the English biologist Francis Crick (Fig. 1.14) and biophysicist Morris Wilkins (1916-2004) discovered the structure of DNA in 1953 (for this they received 1962, awarded the Nobel Prize in Physiology or Medicine), and subsequently discovered the role of nucleic acids in the preservation and transmission of hereditary information.

Rice. 1.15. A.A. Kovalevsky (1840-1901)

Rice. 1.16. I.I. Schmalhausen (1884-1963)

Rice. 1.17. I.I. Mechnikov (1845-1916)

Rice. 1.18. S.G. Navashin (1857-1930)

Two biochemists - the Spaniard Severo Ochoa (1905-1993) and the American Arthur Kornberg (1918-2001) became laureates of the 1959 Nobel Prize in Physiology or Medicine "for the discovery of the mechanisms of RNA and DNA biosynthesis. And during 1961-1965, thanks to the work of the laureates The 1968 Nobel Prize in Physiology or Medicine awarded to American biochemists Marshall Nirenberg (1927-2010), Robert Holley (1922-1993) and Indian biochemist Hara Gobind Khorani (1922-2010) deciphered the genetic code and elucidated its role in protein synthesis.

Genetic and cellular engineering methods are often used in the development of biotechnological processes. Genetic engineering is an applied branch of molecular genetics and biochemistry that develops methods for rearranging the hereditary material of organisms by removing or introducing individual genes or their groups. Genes outside the body were first synthesized in 1969 by H.G. Khorana. In the same year, for the first time, it was possible to isolate the genes of the bacterium Escherichia coli in pure form. Over the past decades, scientists have deciphered the structure of the hereditary material of various organisms (Fly Drosophila, corn, etc.), and humans in particular. This makes it possible to solve many problems, for example, treating various diseases, increasing human lifespan, providing humanity with food, etc.

For their research in the field of biochemistry, two biochemists of German origin received the Nobel Prize in Physiology or Medicine in 1953 - the English Hans Adolf Krebs (1900-1981) and the American Fritz Albert Lipman (1899-1986) for the discovery of the cycle of biochemical reactions during the oxygen stage of energy metabolism (called the Krebs cycle). American chemist Melvin Calvin (1911-1997) studied the steps in the conversion of carbon(II) oxide to carbohydrates during the dark phase of photosynthesis (Kelvin cycle), for which he received the Nobel Prize in Chemistry in 1961. In 1997, the American biochemist Stanley Prusiner (born 1942) was awarded the Nobel Prize in Physiology or Medicine for his study of prions - protein infectious particles that can cause deadly diseases of the brain of humans and farm animals (“mad cow disease”, etc. ).

Ukrainian scientists made an important contribution to the development of biology. In particular, the studies of Alexander Onufrievich Kovalevsky (Fig. 1.15) and Ivan Ivanovich Shmalhausen (Fig. 1.16) played an important role in the development of comparative animal anatomy, phylogeny and evolutionary views. Ilya Ilyich Mechnikov (Fig. 1.17) discovered the phenomenon of phagocytosis and developed the theory of cellular immunity, for which he was awarded the Nobel Prize in Physiology or Medicine in 1908. He also proposed a hypothesis for the origin of multicellular animals. A.A. Kovalevsky and I.I. Mechnikov is rightly considered the founders of evolutionary embryology. The Ukrainian botanical school gained worldwide fame from Sergei Gavrilovich Navashin (Fig. 1.18), who in 1898 discovered the process of double fertilization in flowering plants.

Rice. 1.19. IN AND. Vernadsky (1863-1945)

It is difficult to imagine the modern development of ecology without the works of our outstanding compatriot - Vladimir Ivanovich Vernadsky (Fig. 1.19). He created the doctrine of the biosphere - a single global ecosystem of planet Earth, as well as the noosphere - a new state of the biosphere caused by human mental activity. As often happens, ideas.I. Vernadsky were ahead of their time. Only now his forecasts about the noosphere are considered as a kind of program designed to ensure the harmonious coexistence of man and the natural environment, which is based on the greening of all spheres of human activity: industry, transport, livestock and crop farming. IN AND. Vernadsky founded a new science - biogeochemistry, which studies the biochemical activity of living organisms and the transformation of the geological shells of our planet.

Rice. 1.20. Domestic biologists: A.V. Fomin (1869-1935) (1); N.G. Cold (1882-1953) (2); A.V. Palladin (1885-1972) (3); CM. Gershenzon (1906-1998) (4); O.A. Bogomolets (1881-1946) (5); D.K. Zabolotny (1866-1929) (6); P.G. Kostyuk (1924-2010) (7)