Biology basics cheat sheet. Preparing for the OGE in biology

Biology - a complex of sciences about living nature, which studies the structure and functions of living things, their diversity, origin and development, as well as interaction with the environment.

Classification of biological sciences

Currently in biology composition include botany(plants), zoology(animals), microbiology(microorganisms), mycology(mushrooms), systematics, biochemistry(chemical composition of living matter and chemical processes in it), cytology(cell), histology(fabrics), anatomy(internal structure), physiology(life processes), embryology(individual development), ethology(behavior), genetics(heredity and variability), selection(breeding organisms with properties needed by humans), biotechnology(use of living organisms and biological processes in production), evolutionary doctrine(historical development of the organic world), paleontology(fossil remains), anthropology(historical development of man as a biological species), ecology(populations, communities, biogeocenoses and biosphere).

At the intersection of biology and other sciences, a number of new sciences arose, such as biophysics, biochemistry, bionics and etc.

Biology methods

Main methods of biology are:

• comparative-descriptive,
• modeling (creating simplified simulations of an object or phenomenon),
• monitoring (systematic observation, assessment and forecast of changes in the state of an object),
• light and electron microscopy,
• differential centrifugation, or fractionation (separation of particles under the influence of centrifugal force),
• tagged atom method, or autoradiography, etc.

The role of biology in the formation of the modern natural science picture of the world and in the practical activities of people

Biology played an important role role in the formation of a modern natural science picture of the world , since it reveals the mechanisms of the emergence of the organic world from non-living components and its evolution, proves the unity of its origin based on the structure of cells, and also generalizes the mechanisms of heredity and variability.

Biology makes a significant contribution to human understanding of the scientific picture of the world, based on the systematization of scientific facts established during scientific research and their generalization to the level of theories, rules and laws.

The role of biology in the practical activities of people . The use of adequate modern methods of scientific research has radically transformed biology, expanded its cognitive capabilities and opened new ways for the use of biological knowledge in all spheres of human activity. Thanks to the achievements of biology, medications, vitamins, and biologically active substances are produced industrially. Discoveries made in genetics, anatomy, physiology and biochemistry make it possible to give a sick person a correct diagnosis and develop effective ways to treat and prevent various diseases.

Using knowledge of the laws of heredity and variability, breeding scientists obtain new highly productive breeds of domestic animals and varieties of cultivated plants. Based on the study of relationships between organisms, biological methods for controlling crop pests have been created. The study of the structure and operating principles of various systems of living organisms helped to find original solutions in technology and construction.

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Ticket 1 1.Biology as a science, its achievements, connections with other sciences. Methods for studying living objects. The role of biology in human life and practical activities. 2. The plant kingdom, its differences from other kingdoms of living nature. Explain which group of plants currently occupies a dominant position on Earth. Find representatives of this group among living plants or herbarium specimens. 3.Using knowledge about metabolism and energy conversion in the human body, give a scientific explanation of the effect of physical inactivity, stress, bad habits, and overeating on metabolism.

1. Biology (from Greek bios life, logos science) the science of life. She studies living organisms, their structure, development and origin, relationships with their environment and with other living organisms. 2. Biology - a set of sciences about life, about living nature (see table “System of biological sciences”). I. Biology as a science, its achievements in connection with other sciences. Methods for studying living objects. The role of biology in human life and practical activities.

3. Basic methods in biology 1.observation (allows you to describe biological phenomena), 2.comparison (makes it possible to find general patterns in the structure and life of various organisms), 3.experiment or experience (helps the researcher study the properties of biological objects), 4.modeling (processes that are inaccessible to observation or experimental reproduction are simulated), 5. historical method (based on data about the modern organic world and its past, the processes of development of living nature are learned).

4. Achievements of biology: 1). Description of the large number of species of living organisms existing on Earth; 2). Creation of cellular, evolutionary, chromosome theory; 3). The discovery of the molecular structure of the structural units of heredity (genes) served as the basis for the creation of genetic engineering. 4). The practical application of the achievements of modern biology makes it possible to obtain industrially significant amounts of biologically active substances.

6). Thanks to knowledge of the laws of heredity and variability, great successes have been achieved in agriculture in the creation of new highly productive breeds of domestic animals and varieties of cultivated plants. 5). Based on the study of relationships between organisms, biological methods for controlling crop pests have been created.

7).Great importance in biology is attached to elucidating the mechanisms of protein biosynthesis and the secrets of photosynthesis, which will open the way to obtaining organic nutrients. In addition, the use in industry (in construction, when creating new machines and mechanisms) of the principles of organization of living beings (bionics) brings at present and will give in the future a significant economic effect. The honeycomb design formed the basis for the production of "honeycomb panels" for construction

In such a situation, the only basis for increasing food resources can be the intensification of agriculture. An important role in this process will be played by the development of new highly productive forms of microorganisms, plants and animals, and the rational, scientifically based use of natural resources.

1. Plants are autotrophs and are capable of photosynthesis; 2. The presence of plastids with pigments in the cells; 3. The cells are surrounded by a cellulose wall; 4.Presence of vacuoles with cell sap in the cells; 5.Unlimited growth; 6. There are plant hormones - phytohormones; 7. Osmotic type of nutrition (receipt of nutrients in the form of aqueous solutions entering through the cell membrane).

Angiosperms or flowering plants are the largest division of modern higher plants, numbering about 250 thousand species. They grow in all climatic zones and are part of all biogeocenoses of the globe. This indicates their high adaptability to modern conditions of existence on Earth.

Adaptations in angiosperms (flowering plants) that allowed them to occupy a dominant position on Earth: I. The vegetative organs of flowering plants achieve the greatest complexity and diversity. II. Flowering plants have a more advanced conductive system, which provides better water supply to the plant. III. For the first time, flowering plants have a new organ - the flower. The ovules are enclosed in a closed cavity of the ovary, formed by one or more fused carpels. The seeds are enclosed in the fruit. Double fertilization appeared, which sharply distinguishes them from all other groups of the plant world. IV. The most important transformations took place in the conductive system. Instead of tracheids, vessels become the main conducting elements of the xylem, which significantly accelerates the movement of the ascending current. Thus, angiosperms received additional opportunities in the competition and ultimately became “winners” in the struggle for existence.

III. Using knowledge about metabolism and energy conversion in the human body, give a scientific explanation of the effect of physical inactivity, stress, bad habits, and overeating on metabolism. The body receives many substances from the outside, processes them, obtaining energy or those molecules that the body needs to build its own tissues. The resulting metabolic products are excreted from the body. The totality of all reactions of dissimilation (the breakdown of substances with the release of energy) and assimilation (the synthesis of substances necessary for the body) is called metabolism. In a healthy body, assimilation and dissimilation are strictly balanced. All metabolic reactions are regulated by the nervous and endocrine systems. Metabolic disorders underlie many human diseases.

1. Physical inactivity - reduced physical activity, lack of physical activity - leads to a decrease in the performance of muscles, the cardiovascular system and, as a consequence, metabolic disorders and a deterioration in the condition of the whole organism as a whole. Nutrients not spent on physical activity are stored, which often leads to obesity. Overeating also contributes to this (2).

3. Stress is a protective reaction of the body that allows it to survive in times of danger. Stress mobilizes the body's capabilities, is accompanied by the release of hormones, increases the intensity of cardiovascular activity, etc. However, severe and especially prolonged stress can lead to depletion of human strength and metabolic disorders.

4. Constant consumption of alcoholic beverages has a very strong negative effect on metabolism. In alcoholics, oxidizing ethyl alcohol gives the body a certain amount of energy, but it also produces very toxic substances that kill liver and brain cells. Gradually, the appetite of alcoholics decreases, and they stop eating normal amounts of proteins, fats and carbohydrates, replacing them with alcoholic beverages, which leads to destruction of the body. Chronic alcoholics always have damaged liver, they lose weight, and gradual muscle destruction occurs.

5. Smoking also has a strong negative effect on metabolism, since it destroys the lungs and prevents the body from receiving the required amount of oxygen. In addition, smoking greatly increases the likelihood of developing lung cancer.

6. Narcotic substances, participating in metabolism, cause addiction; subsequently, the cessation of the intake of nicotine, alcohol, etc. is accompanied by withdrawal symptoms - a sharp deterioration in well-being. Thus, physiological and psychological dependence on drugs occurs.

There are a lot of ways in which a person can use knowledge in biology; for example, here are a few (let’s go from largest to smallest):

· Knowledge environmental laws allows you to regulate human activity within the limits of preserving the ecosystem in which he lives and works (rational environmental management);

· Botany and genetics allow you to increase productivity, fight pests and develop new, necessary and useful varieties;

· Genetics is currently so tightly intertwined with medicine that many diseases that were previously considered incurable are studied and prevented already at the embryonic stages of human development;

· With the help of microbiology, scientists around the world are developing serums and vaccines against viruses and a wide variety of antibacterial drugs.

Differences between living structures and nonliving ones. Properties of living things

Biology - a science that studies the properties of living systems. However, defining what a living system is is quite difficult. The line between living and nonliving is not as easy to draw as it seems. Try to answer the questions: Are viruses alive when they rest outside the host’s body and there is no metabolism in them? Can artificial objects and machines exhibit the properties of living things? What about computer programs? Or languages?

To answer these questions, we can try to isolate a minimum set of properties characteristic of living systems. That is why scientists have established several criteria by which an organism can be classified as living.

The most important of characteristic properties (criteria) of living things are the following:

1. Exchange of matter and energy with the environment. From the point of view of physics, all living systems are open, that is, they constantly exchange both matter and energy with the environment, unlike closed completely isolated from the outside world, and semi-closed, exchanging only energy, but not matter. We will see later that this exchange is a prerequisite for the existence of life.

2. Living systems are capable of accumulating substances received from the environment and, as a result, growth.

3. Modern biology considers the fundamental property of living beings to be the ability to create identical (or almost identical) self-reproduction, that is, reproduction while maintaining most of the properties of the original organism.

4. Identical self-reproduction is inextricably linked with the concept heredity, that is, the transmission of traits and properties to offspring.

5. However, heredity is not absolute - if all daughter organisms exactly copied their parents, then no evolution would be possible, since living organisms would never change. This would lead to the fact that with any sudden change in conditions they would all die. But life is extremely flexible, and organisms adapt to a wide range of conditions. This is possible thanks to variability– the fact that the self-reproduction of organisms is not completely identical; during it, errors and variations arise, which can be material for selection. There is a certain balance between heredity and variability.

6. Variability can be hereditary and non-hereditary. Hereditary variability, that is, the appearance of new variations of traits that are inherited and fixed in a number of generations, serves as material for natural selection. Natural selection is possible among any reproducing objects, not necessarily living ones, if there is competition between them for limited resources. Those objects that, due to variability, have acquired unfavorable characteristics in a given environment will be rejected, therefore, characteristics that give a competitive advantage in the fight will be found more and more often in new objects. This is natural selection - the creative factor of evolution, thanks to which all the diversity of living organisms on Earth arose.

7. Living organisms actively respond to external signals, exhibiting the property irritability.

8. Thanks to their ability to respond to changes in external conditions, living organisms are capable of adaptation- adaptation to new conditions. This property, in particular, allows organisms to survive various disasters and spread to new territories.

9. Adaptation is carried out by self-regulation, that is, the ability to maintain the constancy of certain physical and chemical parameters in a living organism, including in changing environmental conditions. For example, the human body maintains a constant temperature, concentration of glucose and many other substances in the blood.

10. An important property of earthly life is discreteness, that is, discontinuity: it is represented by individual individuals, individuals are combined into populations, populations into species, etc., that is, at all levels of organization of living things there are separate units. Stanislaw Lem's science fiction novel Solaris describes a huge living ocean covering the entire planet. But there are no such life forms on Earth.

Chemical composition of living things

Living organisms consist of a huge number of chemical substances, organic and inorganic, polymeric and low molecular weight. Many chemical elements present in the environment are found in living systems, but only about 20 of them are necessary for life. These elements are called biogenic.

In the process of evolution from inorganic to bioorganic substances, the basis for the use of certain chemical elements in the creation of biological systems is natural selection. As a result of this selection, the basis of all living systems consists of only six elements: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, called organogens. Their content in the body reaches 97.4%.

Organogens are the main chemical elements that make up organic substances: carbon, hydrogen, oxygen and nitrogen.

From the point of view of chemistry, the natural selection of organogen elements can be explained by their ability to form chemical bonds: on the one hand, quite strong, that is, energy-intensive, and on the other, quite labile, which could easily succumb to hemolysis, heterolysis, and cyclic redistribution.

The number one organogen is undoubtedly carbon. Its atoms form strong covalent bonds with each other or with atoms of other elements. These bonds can be single or multiple; thanks to these 3 bonds, carbon is able to form conjugated or cumulated systems in the form of open or closed chains and cycles.

Unlike carbon, the organogenic elements hydrogen and oxygen do not form labile bonds, but their presence in an organic, including bioorganic, molecule determines its ability to interact with a biosolvent—water. In addition, hydrogen and oxygen are carriers of the redox properties of living systems; they ensure the unity of redox processes.

The remaining three organogens - nitrogen, phosphorus and sulfur, as well as some other elements - iron, magnesium, which constitute the active centers of enzymes, like carbon, are capable of forming labile bonds. A positive property of organogens is also that they, as a rule, form compounds that are easily soluble in water and therefore concentrate in the body.

There are several classifications of chemical elements contained in the human body. Thus, V.I. Vernadsky, depending on the average content in living organisms, divided the elements into three groups:

1. Macroelements. These are elements whose content in the body is higher than 10 - ²%. These include carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, calcium, magnesium, sodium and chlorine, potassium, and iron. These are the so-called universal biogenic elements present in the cells of all organisms.

2. Microelements. These are elements whose content in the body ranges from 10 - ² to 10 - ¹²%. These include iodine, copper, arsenic, fluorine, bromine, strontium, barium, and cobalt. Although these elements are contained in organisms in extremely low concentrations (not higher than a thousandth of a percent), they are also necessary for normal life. These are biogenic microelements. Their functions and roles are very diverse. Many microelements are part of a number of enzymes, vitamins, respiratory pigments, some affect growth, development rate, reproduction, etc.

3. Ultramicroelements. These are elements whose content in the body is below 10-¹²%. These include mercury, gold, uranium, radium, etc.

V.V. Kovalsky, based on the degree of importance of chemical elements for human life, divided them into three groups:

1. Irreplaceable elements. They are constantly present in the human body and are part of its inorganic and organic compounds. These are H, O, Ca, N, K, P, Na, S, Mg, Cl, C, I, Mn, Cu, Co, Zn, Fe, Mo, V. A deficiency in the content of these elements leads to disruption of the normal functioning of the body.

2. Impurity elements. These elements are constantly present in the human body, but their biological role has not yet always been clarified or has been poorly studied. These are Ga, Sb, Sr, Br, F, B, Be, Li, Si, Sn, Cs, As, Ba, Ge, Rb, Pb, Ra, Bi, Cd, Cr, Ni, Ti, Ag, Th, Hg , Ce, Se.

3. Microimpurity elements. They are found in the human body, but there is no information about their quantitative content or biological role. These are Sc, Tl, In, La, Sm, Pr, W, Re, Tb, etc. The chemical elements necessary for the construction and functioning of cells and organisms are called biogenic.

Among inorganic substances and components, the main place is occupied by - water.

To maintain the ionic strength and pH environment at which vital processes occur, certain concentrations of inorganic ions are necessary. To maintain a certain ionic strength and connection of the buffer medium, the participation of singly charged ions is necessary: ​​ammonium (NH4+); sodium(Na+); potassium (K+). Cations are not interchangeable; there are special mechanisms that maintain the necessary balance between them.

Inorganic compounds:

Ammonium salts;

Carbonates;

Sulfates;

Phosphates.

Nonmetals:

1. Chlorine (basic). In the form of anions, it participates in the creation of a salt environment, and is sometimes part of some organic substances.

2. Iodine and its compounds take part in some vital processes of organic compounds (living organisms). Iodine is part of the thyroid hormones (thyroxine).

3. Selenium derivatives. Selenocesteine ​​is part of some enzymes.

4. Silicon - is part of cartilage and ligaments, in the form of orthosilicic acid esters, takes part in the stitching of polysaccharide chains.

Many compounds in living organisms are complexes: heme is a complex of iron with a flat paraffin molecule; cobolamine

Magnesium and calcium are the main ones metals, not counting iron, are ubiquitous in biological systems. The concentration of magnesium ions is important for maintaining the integrity and functioning of ribosomes, that is, for protein synthesis.

Magnesium is also part of chlorophyll. Calcium ions take part in cellular processes including muscle contractions. Undissolved salts – participate in the formation of supporting structures:

Calcium phosphate (in bones);

Carbonate (in mollusk shells).

Metal ions of the 4th period are part of a number of vital compounds - enzymes. Some proteins contain iron in the form of iron-sulfur clusters. Zinc ions are found in a significant number of enzymes. Manganese is part of a small number of enzymes, but plays an important role in the biosphere, during the photochemical reduction of water, ensures the release of oxygen into the atmosphere and the supply of electrons to the transport chain during photosynthesis.

Cobalt is part of enzymes in the form of cobalamins (vitamin B 12).

Molybdenum is an essential component of the enzyme nitrodinase (which catalyzes the reduction of atmospheric nitrogen to ammonia in nitrogen-fixing bacteria)

Big number organic matter part of living organisms: acetic acid; acetaldehyde; ethanol (are products and substrates of biochemical transformations).

The main groups of low-molecular compounds of living organisms:

Amino acids are components of proteins

Nucleamides are part of nucleic acids

Mono and oligosaccharides are components of structural tissues

Lipids are components of cell walls.

In addition to the previous ones, there are:

Enzyme cofactors are essential components of a significant number of enzymes and catalyze redox reactions.

Coenzymes are organic compounds that function in certain enzyme reaction systems. For example: nicotinoamidodanine dinucleatide (NAD+). In oxidized form, it is an oxidizer of alcohol groups to carbonyl groups, thereby forming a reducing agent.

Enzyme cofactors are complex organic molecules synthesized from complex precursors that must be present as essential components of food.

Higher animals are characterized by the formation and functioning of substances that control the nervous and endocrine systems - hormones and neurotransmitters. For example, the adrenal hormone triggers the oxidative processing of glycogen during a stressful situation.

Many plants synthesize complex amines with strong biological effects - alkaloids.

Terpenes are compounds of plant origin, components of essential oils and resins.

Antibiotics are substances of microbiological origin, secreted by special types of microorganisms that suppress the growth of other competing microorganisms. Their mechanism of action is varied, for example slowing down the growth of proteins in bacteria.

Term "biology" is formed from two Greek words “bios” - life and “logos” - knowledge, teaching, science. Hence the classic definition of biology as a science that studies life in all its manifestations.

Biology explores the diversity of existing and extinct living beings, their structure, functions, origin, evolution, distribution and individual development, connections with each other, between communities and with inanimate nature.

Biology examines general and particular patterns inherent in life in all its manifestations and properties: metabolism, reproduction, heredity, variability, adaptability, growth, development, irritability, mobility, etc.

Research methods in biology

1. Observation- the simplest and most accessible method. For example, you can observe seasonal changes in nature, in the life of plants and animals, animal behavior, etc.
2. Description biological objects (oral or written description).
3. Comparison– finding similarities and differences between organisms, used in taxonomy.
4. Experimental method(in laboratory or natural conditions) – biological research using various instruments and methods of physics and chemistry.
5. Microscopy– study of the structure of cells and cellular structures using light and electron microscopes. Light microscopes allow you to see the shapes and sizes of cells and individual organelles. Electronic – small structures of individual organelles.
6. Biochemical method- study of the chemical composition of cells and tissues of living organisms.
7. Cytogenetic– a method of studying chromosomes under a microscope. You can detect genomic mutations (for example, Down syndrome), chromosomal mutations (changes in the shape and size of chromosomes).
8. Ultracentrifugation- isolation of individual cellular structures (organelles) and their further study.
9. Historical method– comparison of the obtained facts with previously obtained results.
10. Modeling– creation of various models of processes, structures, ecosystems, etc. in order to predict changes.
11. Hybridological method– the method of crossing, the main method of studying the patterns of heredity.
12. Genealogical method– a method of compiling pedigrees, used to determine the type of inheritance of a trait.
13. Twin method– a method that allows you to determine the share of influence of environmental factors on the development of traits. Applies to identical twins.

Connection of biology with other sciences.

The diversity of living nature is so great that modern biology must be presented as a complex of sciences. Biology underlies such sciences as medicine, ecology, genetics, selection, botany, zoology, anatomy, physiology, microbiology, embryology etc. Biology, together with other sciences, formed such sciences as biophysics, biochemistry, bionics, geobotany, zoogeography, etc. In connection with the rapid development of science and technology, new directions in the study of living organisms are emerging, and new sciences related to biology are appearing. This once again proves that the living world is multifaceted and complex and it is closely connected with inanimate nature.

Basic biological sciences - objects of their study

1. Anatomy is the external and internal structure of organisms.
2. Physiology – life processes.
3. Medicine - human diseases, their causes and methods of treatment.
4. Ecology – relationships between organisms in nature, patterns of processes in ecosystems.
5. Genetics - the laws of heredity and variability.
6. Cytology is the science of cells (structure, vital activity, etc.).
7. Biochemistry – biochemical processes in living organisms.
8. Biophysics – physical phenomena in living organisms.
9. Breeding is the creation of new and improvement of existing varieties, breeds, strains.
10. Paleontology – fossil remains of ancient organisms.
11. Embryology - development of embryos.

A person can apply knowledge in the field of biology:

• for the prevention and treatment of diseases
• when providing first aid victims of accidents;
• in crop production, livestock farming
• in environmental activities that contribute to solving global environmental problems (knowledge about the interrelations of organisms in nature, about factors that negatively affect the state of the environment, etc.). BIOLOGY AS A SCIENCE

Signs and properties of living things:

1. Cellular structure. The cell is a single structural and functional unit, as well as a unit of development for almost all living organisms on Earth. Viruses are an exception, but even they exhibit living properties only when they are in a cell. Outside the cell they do not show any signs of life.

2. Unity of chemical composition. Living things are made up of the same chemical elements as non-living things, but in living things 90% of the mass comes from four elements: S, O, N, N, which are involved in the formation of complex organic molecules, such as proteins, nucleic acids, carbohydrates, lipids.

3. Metabolism and energy are the main properties of living things. It is carried out as a result of two interrelated processes: the synthesis of organic substances in the body (due to external sources of energy from light and food) and the process of decomposition of complex organic substances with the release of energy, which is then consumed by the body. Metabolism ensures the constancy of the chemical composition in continuously changing environmental conditions.

4. Openness. All living organisms are open systems, i.e. systems that are stable only if they receive continuous energy and matter from the environment.

5. Self-reproduction (reproduction). The ability to self-reproduce is the most important property of all living organisms. It is based on information about the structure and functions of any living organism, embedded in nucleic acids and ensuring the specificity of the structure and vital activity of the living organism.

6. Self-regulation. Thanks to the mechanisms of self-regulation, the relative constancy of the internal environment of the body is maintained, i.e. the constancy of the chemical composition and the intensity of the physiological processes are maintained - homeostasis.

7. Development and growth. In the process of individual development (ontogenesis), the individual properties of the organism gradually and consistently appear (development) and its growth occurs (increase in size). In addition, all living systems evolve - change during historical development (phylogeny).

8. Irritability. Any living organism is capable of responding to external and internal influences.

9. Heredity. All living organisms are capable of preserving and transmitting basic characteristics to offspring.

10. Variability. All living organisms are capable of changing and acquiring new characteristics.

Basic levels of organization of living nature

All living nature is a collection of biological systems. Important properties of living systems are multilevel and hierarchical organization. The parts of biological systems are themselves systems made up of interconnected parts. At every level, every biological system is unique and different from other systems.

Scientists, based on the characteristics of the manifestation of the properties of living things, have identified several levels of organization of living nature:

1. Molecular level - represented by molecules of organic substances (proteins, lipids, carbohydrates, etc.) found in cells. At the molecular level, one can study the properties and structures of biological molecules, their role in the cell, in the life of the organism, and so on. For example, doubling the DNA molecule, protein structure, and so on.

2. Cellular level – represented by cells. At the cellular level, the properties and signs of living things begin to appear. At the cellular level, one can study the structure and functions of cells and cellular structures, the processes occurring in them. For example, the movement of the cytoplasm, cell division, protein biosynthesis in ribosomes, and so on.

3. Organ-tissue level – represented by tissues and organs of multicellular organisms. At this level, one can study the structure and functions of tissues and organs, the processes occurring in them. For example, contraction of the heart, movement of water and salts through vessels, and so on.

4. Organismal level – represented by unicellular and multicellular organisms. At this level, the organism is studied as a whole: its structure and vital functions, mechanisms of self-regulation of processes, adaptation to living conditions, and so on.

5. Population-species level– represented by populations consisting of individuals of the same species living together for a long time in a certain territory. The life of one individual is genetically determined, and under favorable conditions the population can exist indefinitely. Since at this level the driving forces of evolution begin to operate - the struggle for existence, natural selection, etc. At the population-species level, they study the dynamics of the number of individuals, the age-sex composition of the population, evolutionary changes in the population, and so on.

6. Ecosystem level– represented by populations of different species living together in a certain territory. At this level, the relationships between organisms and the environment, the conditions that determine the productivity and sustainability of ecosystems, changes in ecosystems, and so on are studied.

7. Biosphere level– the highest form of organization of living matter, uniting all ecosystems of the planet. At this level, processes are studied on the scale of the entire planet - cycles of matter and energy in nature, global environmental problems, changes in the Earth's climate, etc. Currently, the study of human influence on the state of the biosphere in order to prevent a global environmental crisis is of paramount importance.

THEORETICAL MATERIAL

BIOLOGY AS A SCIENCE. METHODS OF BIOLOGY

Biology - the science of life, its patterns and forms of manifestation, its existence and distribution in time and space. She explores the origins of life and its essence, development, interconnections and diversity. Biology belongs to the natural sciences.

The term “biology” was first used by the German professor of anatomy T. Ruz in 1779. However, it became generally accepted in 1802, after the French naturalist J.-B. began to use it in his works. Lamarck.

Modern biology is a complex science, consisting of a number of independent scientific disciplines with their own objects of research.

BIOLOGICAL DISCIPLINES

Botany- plant science,

Zoology- animal science,

Mycology- about mushrooms,

Virology- about viruses,

Microbiology- about bacteria.

Anatomy- a science that studies the internal structure of organisms (individual organs, tissues). Plant anatomy studies the structure of plants, animal anatomy studies the structure of animals.

Morphology- a science that studies the external structure of organisms

Physiology- a science that studies the vital processes of the body and the functions of individual organs.

Hygiene- the science of preserving and strengthening human health.

Cytology- cell science.

Histology- tissue science.

Taxonomy- the science of classifying living organisms. Classification is the division of organisms into groups (species, genus, families, etc.) based on structural features, origin, development, etc.

Paleontology- a science that studies the fossil remains (imprints, fossils, etc.) of organisms.

Embryology- the science that studies the individual (embryo) development of organisms.

Ecology- a science that studies the relationships of organisms with each other and with the environment.

Ethology- the science of animal behavior.

Genetics- the science of the laws of heredity and variability.

Selection- the science of breeding new and improving existing breeds of domestic animals, varieties of cultivated plants and strains of bacteria and fungi.

Evolutionary doctrine- studies the origins and laws of the historical development of life on Earth.

Anthropology- the science of the emergence and development of man.

Cell engineering- a branch of science dealing with the production of hybrid cells. An example is the hybridization of cancer cells and lymphocytes, the fusion of protoplasts of different plant cells, and cloning.

Genetic Engineering- a branch of science that deals with the production of hybrid DNA or RNA molecules. If cell engineering works at the cellular level, then genetic engineering works at the molecular level. In this case, specialists “transplant” the genes of one organism to another. One of the results of genetic engineering is the production of genetically modified organisms (GMOs).

Bionics- a direction in science that searches for opportunities to apply the principles of organization, properties and structures of living nature in technical devices.

Biotechnology- a discipline that studies the possibilities of using organisms or biological processes to obtain substances needed by humans. Typically, biotechnological processes use bacteria and fungi.

GENERAL METHODS OF BIOLOGY

A method is a way of understanding reality.

1. Observation and description.

2.Measurement

3. Comparison

4. Experiment or experience

5. Simulation

6. Historical.

STAGES OF SCIENTIFIC RESEARCH

Held observation over an object or phenomenon

based on the data obtained, it is put forward hypothesis

scientific experiment(with control experience)

a hypothesis tested during an experiment can be called
theory or by law

PROPERTIES OF LIVING

Metabolism and energy flow- the most important property of living things. All living organisms absorb the substances they need from the external environment and release waste products into it.

Unity of chemical composition. Among the chemical elements in living organisms, carbon, oxygen, hydrogen and nitrogen predominate. In addition, the most important feature of living organisms is the presence of organic substances: fats, carbohydrates, proteins and nucleic acids.

Cellular structure. All organisms are made up of cells. Only viruses have a non-cellular structure, but they also show signs of being alive only after entering the host cell.

Irritability- the body’s ability to respond to external or internal influences.

Self-reproduction. All living organisms are capable of reproduction, that is, the reproduction of their own kind. Reproduction of organisms occurs in accordance with the genetic program recorded in DNA molecules.

Heredity and variability.

Heredity is the ability of organisms to pass on their characteristics to their descendants. Heredity ensures continuity of life. Variability is the ability of organisms to acquire new characteristics in the process of their development. Hereditary variability is an important factor in evolution.

Growth and development.

Growth - quantitative changes (for example, increase in mass).

Development - qualitative changes (for example, the formation of organ systems, flowering and fruiting).

Self-regulation - the ability of organisms to maintain the constancy of their chemical composition and vital processes - homeostasis.

Adaptation

Rhythm - periodic changes in the intensity of physiological functions with different periods of fluctuations (daily, seasonal rhythms). (For example, photoperiodism is the body’s reaction to the length of daylight hours).

Levels of life organization

Test tasks in OGE format

What science studies the varietal diversity of plants?

1)physiology 2)systematics 3)ecology 4)selection

2. You can find out whether light is necessary for the formation of starch in leaves using

1) descriptions of plant organs 2) comparisons of plants from different natural zones

3) observations of plant growth 4) photosynthesis experiment

3. In what area of ​​biology was cell theory developed?

1) virology 2) cytology 3) anatomy 4) embryology

4. To separate cell organelles by density, you will choose a method

1) observation 2) chromatography 3) centrifugation 4) evaporation

5. The photograph shows a model of a DNA fragment. What method allowed scientists to create such a three-dimensional image of a molecule?

1) classification 2) experiment 3) observation 4) modeling

6. The photo shows a ball-and-stick DNA fragment. What method allowed scientists to create such a three-dimensional image of a molecule?

classification 2) experiment 3) observation 4) modeling

7. The use of which scientific method illustrates the plot of the painting by the Dutch artist J. Steen “Pulse”, written in the middle of the 17th century?

1) modeling 2) measurement 3) experiment 4) observation

8. Study the graph reflecting the process of growth and development of the insect.

Determine the length of the insect on the 30th day of its development.

1) 3,4 2) 2,8 3) 2,5 4) 2,0

9. Which of the following scientists is considered the creator of the doctrine of evolution?

1) I.I. Mechnikov 2) L. Pasteur 3) Ch. Darwin 4) I.P. Pavlova

10. What science studies the varietal diversity of plants?

1) physiology 2) taxonomy 3) ecology 4) selection

11. Select a pair of animals whose experiments have led to major discoveries in animal and human physiology.

1) horse and cow 2) bee and butterfly 3) dog and frog 4) lizard and dove

12. In what area of ​​biology was cell theory developed?

1) virology 2) cytology 3) anatomy 4) embryology

13. You can accurately determine the degree of influence of fertilizers on plant growth using the method

1) experiment 2) modeling 3) analysis 4) observation

14. An example of the application of an experimental research method is

1) description of the structure of a new plant organism

2) comparison of two microslides with different tissues

3) counting a person’s pulse before and after exercise

4) formulating a position based on the facts obtained

15. A microbiologist wanted to find out how quickly one type of bacteria multiplies in different nutrient media. He took two flasks, filled them halfway with different nutrient media and placed approximately the same number of bacteria in them. Every 20 minutes he removed samples and counted the number of bacteria in them. The data from his research are reflected in the table.

Study the table “Change in the rate of reproduction of bacteria over a certain time” and answer the questions.

Change in the rate of bacterial reproduction over a certain time

1) How many bacteria did the scientist put in each flask at the very beginning of the experiment?

2) How did the rate of bacterial reproduction change during the experiment in each flask?

3) How can we explain the results obtained?

Literature

Kamensky A.A., Kriksunov E.A., Pasechnik V.V. Biology. General biology 9th grade: textbook. for educational institutions. M.: Bustard, 2013.

Zayats R.G., Rachkovskaya I.V., Butilovsky V.E., Davydov V.V. Biology for applicants: questions, answers, tests, tasks. - Minsk: Unipress, 2011. - 768 p.

“I will solve the OGE”: biology. Dmitry Gushchin's training system [Electronic resource] - URL: http:// oge.sdamgia.ru