OPTION – 1.

1. The main merit of Charles Darwin is:

A) formulation of the biogenetic law; C) development of the theory of natural selection;

B) creation of the first evolutionary theory; D) creation of the law of natural series.

2. Charles Darwin considered the most intense form of struggle for existence:

A) fight against unfavorable conditions; B) interspecific;

B) intraspecific; D) all of the above forms equally.

3. Natural selection operates at the level of:

A) a separate organism; B) type;

B) populations; D) biocenosis.

4. Homologous organs are:

A) a cat’s paw and a fly’s leg; C) reptile scales and bird feathers;

B) human eye and spider eye; D) butterfly wing and bird wing.

5. Ape people include:

A) Cro-Magnon; B) Pithecanthropus;

B) Australopithecus; D) Neanderthal.

6. Environmental factor beyond endurance limits is called:

A) stimulating; B) abiotic;

B) limiting; D) anthropogenic

7. Eukaryotes:

A) capable of chemosynthesis; C) do not have many organelles;

B) have circular DNA; D) have a core with its own shell.

8. A common feature plant and animal cell is:

A) heterotrophy; B) the presence of chloroplasts;

B) the presence of mitochondria; D) the presence of a rigid cell wall.

9. Biopolymers are:

A) proteins; IN) nucleic acids;

B) polysaccharides; D) all of the above.

10. Uracil forms a complementary bond with:

A) adenine B) cytosine

B) thymine D) guanine.

11. Glycolysis is called:

A) the totality of all processes energy metabolism in a cage;

B) oxygen-free breakdown of glucose;

B) complete breakdown of glucose; D) polymerization of glucose to form glycogen.

12. The order of the mitosis stage is as follows:

A) metaphase, telophase, prophase, anaphase; B) prophase, metaphase, telophase, anaphase;

B) prophase, metaphase, anaphase, telophase; D) telophase, prophase, metaphase, anaphase;

13. Chromosome duplication occurs in:

A) interphase B) metaphase

B) prophase D) telophase

14. In anaphase of mitosis, divergence occurs:

A) daughter chromosomes B) non-homologous chromosomes

B) homologous chromosomes D) cell organelles.

15. Of the animals listed, the largest egg is in:

A) sturgeon B) lizards

B) frogs D) chickens.

16. from the ectoderm are formed:

A) muscles B) skeleton

B) lungs D) sense organs.

17. In a Mendeleev monohybrid cross, the proportion of individuals with at least one recessive gene in the second generation will be equal to:

A) 25% B) 50% C) 75% D) 100%

18. Genes located in:

A) one chromosome B) sex chromosomes

B) homologous chromosomes D) autosomes.

19. Mutations manifest themselves phenotypically:

A) always B) only in a homozygous state

B) only in a heterozygous state D) never.

20. Polyploidy consists of:

A) change in the number of individual chromosomes B) change in the structure of chromosomes

B) multiple change in the haploid number of chromosomes; D) changes in the structure of individual genes.

ANSWER: 1 – C, 2 – B, 3 – B, 4 – C, 5 – C, 6 – B, 7 – D, 8 – B, 9 – D, 10 – A, 11 – B, 12 – B, 13 - A, 14 - A, 15 - G, 16 - G, 17 - B, 18 - A, 19 - B, 20 - B.

Biology test for grade 11. (1)

OPTION – 2

1. According to Charles Darwin, the driving forces of evolution are:

A) struggle for existence; B) natural selection;

B) hereditary variability; D) all of the above.

2. The leading role in evolution is played by the following type of variability:

A) certain; B) group;

B) modification; D) mutational.

3. The driving form of selection usually leads to:

A) destruction of individuals with deviations; B) expansion of the previous norm of reaction;

from the previous norm of reaction;

B) narrowing of the previous norm of reaction; D) a shift in the previous norm of reaction.

4. Similar bodies are:

A) crayfish gills and fish gills; C) birch leaves and cactus needles;

B) a dog’s paw and a bird’s wing; D) all of the listed pairs.

5. During the Ice Age there lived:

A) Cro-Magnons; B) synanthropes;

B) Neanderthals; D) all of the above.

6. Ecosystem productivity is called:

A) her total biomass; B) total biomass of producers;

B) the increase in this biomass per unit of time; D) total biomass of consumers.

7.Prokaryotic cells contain:

A) kernels; B) mitochondria;

B) ribosomes; D) all of the listed organelles.

8. Leukoplasts are cell organelles in which:

A) protein synthesis occurs; C) there are red and red pigments yellow color;

B) the process of photosynthesis is carried out; D) starch accumulates.

9. Nucleotides in a strand of a DNA molecule are connected by the following bond:

A) covalent; B) peptide;

B) hydrogen; D) disulfide bridges.

10. Transcription is:

A) synthesis of mRNA molecules B) delivery of amino acids to ribosomes

according to the matrix of one of the DNA chains; during protein synthesis;

B) transfer of information from mRNA to protein D) process of assembly of a protein molecule.

during its synthesis;

11. ATP synthesis in the cell occurs in the process:

A) glycolysis; B) cellular respiration;

B) photosynthesis; D) all of the above.

12.The longest phase of mitosis is:

A) prophase; B) anaphase;

B) metaphase; D) telophase.

13. Reduction in the number of chromosomes occurs during:

A) anaphase of mitosis; B) II division of meiosis;

B) I division of meiosis; D) in all of the above cases.

14. Biological significance meiosis is to ensure:

A) genetic stability; B) genetic variability;

B) tissue regeneration and increase D) asexual reproduction.

number of cells in the body;

15. The nervous system is formed from:

A) ectoderm; B) mesoderm;

B) endoderm; D) there is no correct answer.

16. From the mesoderm are formed:

A) lungs; IN) circulatory system;

B) nervous system; D) sense organs.

17. How many types of gametes are formed by diheterozygous individuals:

A) one; B) four;

B) two; D) there is no correct answer.

18. Mutational variability includes:

A) changes in chromosomes; B) changes that are inherited;

B) changes in genes; D) all of the above.

19. The main source of combinative variability is:

A) chromosome crossing B) independent chromatid segregation

In prophase I of the meiotic division; in anaphase II of meiotic division;

B) independent divergence D) all of the above processes to an equal extent.

homologous chromosomes

in anaphase I of the meiotic division;

20. Interline hybridization of cultivated plants leads to:

A) maintaining the same productivity; B) increasing productivity;

B) the emergence of new characteristics; D) consolidation of signs.

ANSWER: 1 - G, 2 - G, 3 - G, 4 - A, 5 - B, 6 - B, 7 - B, 8 - G, 9 - A, 10 - A, 11 - G, 12 - A, 13 – B, 14 – V, 15 – A, 16 – V, 17 – V, 18 – D, 19 – D, 20 – V.

OPTION – 1.

1. Deoxyribonucleic acid is the level of organization of living nature:

A) cellular; B) molecular;

B) organismic; D) population

2. The science of cytology studies:

A) the structure of cells of unicellular and multicellular organisms;

B) the structure of organs and organ systems of multicellular organisms;

C) the phenotype of organisms of different kingdoms;

D) morphology of plants and features of their development.

3. Proteins are synthesized in cells:

A) in the cytoplasm; B) in lysosomes;

B) on ribosomes; D) in the Golgi complex.

4. Proteins that can accelerate chemical reactions, perform the following function in the cell:

A) hormonal B) signaling

C) enzymatic D) informational.

5. Transfer RNA is:

A) protein B) fat

C) enzyme D) nucleic acid.

6. Chromosome conjugation is characteristic of the process:

A) fertilization B) prophase of the second division of meiosis

C) mitosis D) prophase of the first division of meiosis

7. The blastula consists of a cavity and:

A) two layers of cells B) connective tissue

C) one layer of cells D) epithelial tissue.

8. Which cells transmit mutations to their offspring during sexual reproduction:

A) epithelial B) muscle

C) gametes D) neurons.

9. Ancient people include:

A) Neanderthal B) Pithecanthropus

C) Sinanthropus D) Cro-Magnon.

10. There is competition between elk and bison because they:

A) eat similar foods; B) have approximately the same body parameters

B) have few offspring; D) belong to the class of mammals.

11. Agroecosystems include:

A) mixed forest B) water meadow

C) an overgrown lake D) a wheat field.

12. Adaptation in the process of evolution arises as a result of:

A) geographic isolation B) interaction of the driving forces of evolution

C) mutational variability D) artificial selection.

13. Cytoplasm in a cell does not fulfill function:

A) transport of substances B) internal environment

C) communication between the nucleus and organelles; D) photosynthesis.

14. Ability plasma membrane surrounding a solid food particle and moving it inside the cell is the basis of the process:

A) diffusion B) osmosis

C) phagocytosis D) pinocytosis.

15. Where does the anaerobic stage of glycolysis take place?

A) in mitochondria B) in the lungs

C) in the digestive tube D) in the cytoplasm.

16. An individual with the Aabv genotype produces gametes:

A) Av, vv B) Av, av

B) Aa, AA D) Aa, vv.

17. When crossing heterozygous plants with red and round fruits with individuals recessive for both characteristics (red A and round IN– dominant traits) offspring will appear with genotypes AaBb, aaBb, AaBb, aaBb in the ratio:

A) 3:1, B) 9:3:3:1

C) 1:1:1:1 D) 1:2:1.

18. A girl develops from an egg if, during the process of fertilization, the following chromosomes appear in the zygote:

A) 44 autosomes +XY B) 23 autosomes +X

C) 44 autosomes +XX D) 23 autosomes +Y.

19. A significant portion of mutations does not appear in the phenotype of the offspring, since they6

A) not associated with gene changes B) not associated with chromosome changes

C) are dominant in nature D) are recessive in nature.

20. A body of water inhabited by various species of plants and animals is:

A) biogeocenosis B) noosphere

C) biosphere D) agroecosystem.

Answers: 1 – B, 2 – A, 3 – B, 4 – C, 5 – G, 6 – G, 7 – B, 8 – C, 9 – A, 10 – A, 11 – G, 12 – B, 13 – G, 14 – C, 15 – G, 16 – B, 17 – C, 18 – C, 19 – G, 20 – A.

Biology test for grade 11. (2)

OPTION – 2

1. To identify general anatomical features characteristic of the kingdom of living nature, use the method:

A) microscopy B) forecasting

C) comparison D) modeling

2. according to cell theory Eukaryotic cells must have:

A) cell wall B) nucleus

C) vacuoles D) plastids

3. During the process of cell division, the most significant transformations undergo:

A) ribosomes B) chromosomes

C) mitochondria D) lysosomes

4. The structure of the DNA molecule is:

A) two polynucleotide strands twisted helically around each other

B) one helically twisted polynucleotide strand

B) two helically twisted polypeptide strands

D) one straight polypeptide strand.

5. On preparatory stage energy metabolism energy:

A) absorbed as heat B) released as heat

C) is absorbed into the cytoplasm of the cell D) is released due to the breakdown of ATP.

6. “The predominant characteristic of one of the parents” G. Mendel called:

A) recessive B) dominant

C) homozygous D) heterozygous

7. When crossing a heterozygote with a homozygote, the proportion of homozygotes in the offspring will be:

A) 0% B) 25% C) 50% D) 100%

8. Changes that are not transmitted inherited and arise as adaptations to the external environment, called:

A) uncertain B) individual

C) mutational D) modification.

9. Law homologous series in hereditary variability was established:

A) V.I. Vernadsky B) I.V. Michurin

B) N.I. Vavilov D) T. Morgan.

10. The presence in humans, as in other mammals, of viviparity and feeding of young with milk indicates:

A) about more high level human development; B) about their divergent evolution

C) about the historical development of the class of mammals; D) about their relationship.

11. Metabolism in a cell consists of the following processes:

A) excitation and inhibition B) plastic and energy metabolism

C) growth and development D) transport of hormones and vitamins.

12. Producers in ecosystems include:

C) saprophytic bacteria D) fungi.

13. New species in nature arise as a result of interaction:

A) hereditary variability, struggle for existence, natural selection

B) non-hereditary changes and seasonal changes in nature

B) fitness of organisms and artificial selection

D) abiotic environmental factors

14. The main reason for the biological regression of many species at present is:

A) climate change B) economic activity person

C) change in relief D) increase in the number of predators.

15. The nucleus plays an important role in the cell, as it participates in the synthesis of:

A) glucose B) fiber

C) lipids D) nucleic acids.

16. Substances capable of forming with water in a living organism hydrogen bonds or enter into electrostatic interaction are:

A) hydrophobic B) hydrophilic

C) neutral D) alkaline.

17. In the oxygen-free stage of energy metabolism, molecules are broken down:

A) glucose to pyruvic acid B) protein to amino acids

C) starch to glucose D) pyruvic acid to carbon dioxide and water

18. When dividing animal and plant cells, the main source of energy is molecules:

A) ATP B) tRNA C) mRNA D) DNA.

19. Diversity of underwater and above-water arrowhead leaves - example:

A) modification variability B) action of mutagens

C) combinative variability D) differences in the genotypes of different cells

20. In human evolution, the initial milestones in the development of art were found among:

A) Neanderthals B) Cro-Magnons

B) Australopithecus Pithecanthropus

Answers: 1 – C, 2 – B, 3 – B, 4 – A, 5 – B, 6 – B, 7 – C, 8 – D, 9 – C, 10 – D, 11 – B, 12 – A, 13 – A, 14 – B, 15 – D, 16 – B, 17 – A, 18 – A, 19 – A, 20 – B.

Lesson 2 VIEW, ITS CRITERIA

Goals: form a concept about the type, structure of the type, criteria; teach how to describe individuals of species morphological criterion.

Equipment: indoor plants for laboratory work.

Lesson progress

I . Knowledge test.

1. Testing.

1) Charles Darwin called hereditary variability:

a) modification;

b) group;

c) uncertain;

d) certain.

2) The driving force of evolution (according to Charles Darwin) of species is:

a) artificial selection;

c) population waves;

d) struggle for existence.

3) The material for evolution is:

a) struggle for existence;

b)naturalselection;

V) modification variability;

d) hereditary variability.

4) Indicate the incorrect statement: “The result of natural selection is...”:

c) hereditary variability;

d) formation of new species.

5) The main merit of Charles Darwin is:

a) in the formulation of the biogenetic law;

b) creation of the first evolutionary theory;

c) development of the theory of natural selection;

d) creation of the law of hereditary series.

6) According to Charles Darwin, the driving forces of evolution are:

a) struggle for existence;

b) hereditary variability;

c) natural selection;

d) all of the above.

7) The leading role in evolution is played by the following type of variability:

a) certain;

b) modification;

c) group;

d) mutational.

8) The ability of organisms to produce large number descendants and limited habitats and life resources are the immediate causes:

a) hereditary variability;

b) struggle for existence;

c) extinction;

d) speciation.

9) Hereditary variability in the process of evolution:

a) create new species;

b) supplies material for evolution;

c) consolidates the material created in the process of evolution;

d) saves the most useful changes.

10) The result of natural selection is not:

a) the adaptability of organisms to their environment;

b) diversity organic world;

c) struggle for existence;

d) improving the organization of living beings.

2. Exercise.

Indicate the numbers of the sentences in which errors were made, correct them:

1) Not all(All)organisms are changeable.

2) All(not all)differences between organisms are necessarily inherited.

3) Organisms reproduce in arithmetic(geometric)progression, and everyone survives to a sexually mature state.

4) Life resources are not limited(limited)and in the struggle for existence only sick, weakened individuals die(not only, but also less adapted).

5) As a result of the struggle for existence, natural selection occurs - those individuals that have properties that are useful in other conditions survive.

3. Exercise.

Match the name of the scientist with his contribution to biology.

Scientist's name

1.4. Lyell

2. Aristotle

3. K. Linnaeus

4. K. Baer 5.4. Darwin

Merits of scientists

a) Described more than 500 species of plants and animals, arranging them in a certain order.

b) When classifying, I used the principle of subordination of systematic categories.

c) Formulated the law of germinal similarity.

d) While studying the geological history of the Earth, he put forward the idea of ​​the driving factors in the evolution of the Earth.

e) Revealed the driving forces and identified the reasons for the occurrence of biological evolution.

4. Oral answers at the board on questions at the end of § 52, No. 3,4.

II . Learning new material.

1. View.

Biological species- this is a set of individuals that have the ability to interbreed with the formation of fertile offspring; inhabiting a certain area; possessing a number of common morphological and physiological characteristics and similarities in relationships with the biotic and abiotic environment.

The species is characterized by integrity and isolation. The integrity of the species is manifested in the fact that its individuals can live and reproduce only by interacting with each other - thanks to the mutual adaptations of organisms developed in the process of evolution: the peculiarities of the coordination of the structure of the maternal organism and the embryo, signaling and perception systems in animals, common territory and etc.

The isolation of the species is maintained by reproductive isolation, which prevents it from mixing with other species during reproduction. Isolation is ensured by differences in the structure of the genital organs, the disunity of the ar. discrepancies in timing or places of reproduction, differences in behavior, etc. Thanks to isolation, species do not mix with each other.

2. Type criteria.

Characteristic signs and the properties by which some species differ from others are called species criteria.

Morphological Physiological Biochemical

Signs of the species

Genetic Environmental Geographical Historical

. Morphological criterion.

The morphological criterion is based on the similarity of the external and internal structure of individuals of the same species.

But individuals within a species are sometimes so variable that it is not always possible to determine the species using morphological criteria alone. At the same time, there are species that are morphologically similar, but individuals of such species do not interbreed. These are twin species.

. Genetic criterion.

This refers to the set of chromosomes characteristic of a particular species. Species usually differ in the number of chromosomes or in the features of their structure, so the genetic criterion is quite reliable. However, it is not absolute either. There are cases when species have chromosomes that are practically indistinguishable in structure. In addition, chromosomal mutations may be widespread within a species, making its precise identification difficult.

. Physiological criterion.

It is based on the similarity of all life processes of individuals of the same species, primarily the similarity of reproduction. Representatives different types, as a rule, do not interbreed, or their offspring are infertile. The non-crossing of species is explained by differences in the structure of the reproductive apparatus, timing of reproduction, etc. However, in nature there are species that cross and produce fertile offspring (some species of canaries, finches, poplars). Consequently, the physiological criterion is insufficient to determine the species identity of individuals.

. Geographical criterion.

This is a specific area occupied by a species in nature.

. Ecological criterion.

Warp ecological criterion- a combination of factors external environment, in which the species exists. For example, caustic buttercup is common in meadows and fields; creeping buttercup grows in damper places; Along the banks of rivers and ponds, in swampy places, burning buttercup is found.

. Biochemical criterion.

The biochemical criterion allows you to distinguish between species according to biochemical parameters (composition and structure of certain proteins, nucleic acids and other substances).

. Historical criterion.

Community of ancestors, a common history of the origin and development of the species.

None of the criteria alone can serve to determine the species. A species can only be characterized by their totality.

III. Consolidation.

Laboratory work

Topic: MORPHOLOGICAL FEATURES OF DIFFERENT SPECIES OF PLANTS

Goals: ensure that students master the concept of a morphological criterion of a species; consolidate the ability to compose descriptive characteristics of plants.

Equipment: live plants or herbarium materials of plants of different species.

Work progress

1. Consider two types of plants, write down their names, make a morphological characteristic of plants of each type, that is, describe their features external structure(features of leaves, stems, roots, flowers, fruits).

2. Compare plants of two types, identify similarities and differences. What explains the similarities (differences) between plants?

Homework: § 53. Written assignment: make lists of plant and animal species known to you, group the species known to you according to the degree of similarity: a) morphological, b) ecological.

Biology test OPTION – 1. 1. The main merit of Charles Darwin is: A) the formulation of the biogenetic law; C) development of the theory of natural selection; B) creation of the first evolutionary theory; D) creation of the law of natural series. 2. Most...

Biology test OPTION – 1. 1. The main merit of Charles Darwin is: A) the formulation of the biogenetic law; C) development of the theory of natural selection; B) creation of the first evolutionary theory; D) creation of the law of natural series. 2. Charles Darwin considered the most intense form of struggle for existence: A) struggle with unfavorable conditions; B) interspecific; B) intraspecific; D) all of the above forms equally. 3. Natural selection operates at the level of: A) an individual organism; B) type; B) populations; D) biocenosis. 4. Homologous organs are: A) a cat’s paw and a fly’s leg; C) reptile scales and bird feathers; B) human eye and spider eye; D) butterfly wing and bird wing. 5. Ape-men include: A) Cro-Magnon man; B) Pithecanthropus; B) Australopithecus; D) Neanderthal. 6. An environmental factor that goes beyond endurance is called: A) stimulating; B) abiotic; B) limiting; D) anthropogenic 7. Eukaryotes: A) capable of chemosynthesis; C) do not have many organelles;

Biology test OPTION – 1. 1. The main merit of Charles Darwin is: A) the formulation of the biogenetic law; C) development of the theory of natural selection; B) creation of the first evolutionary theory; D) creation of the law of natural series. 2. Charles Darwin considered the most intense form of struggle for existence: A) struggle with unfavorable conditions; B) interspecific; B) intraspecific; D) all of the above forms equally. 3. Natural selection operates at the level of: A) an individual organism; B) type; B) populations; D) biocenosis. 4. Homologous organs are: A) a cat’s paw and a fly’s leg; C) reptile scales and bird feathers; B) human eye and spider eye; D) butterfly wing and bird wing. 5. Ape-men include: A) Cro-Magnon man; B) Pithecanthropus; B) Australopithecus; D) Neanderthal. 6. An environmental factor that goes beyond endurance is called: A) stimulating; B) abiotic; B) limiting; D) anthropogenic 7. Eukaryotes: A) capable of chemosynthesis; C) do not have many organelles; B) have circular DNA; D) have a core with its own shell. 8. A common feature of plant and animal cells is: A) heterotrophy; B) the presence of chloroplasts; B) the presence of mitochondria; D) the presence of a rigid cell wall. 9. Biopolymers are: A) proteins; B) nucleic acids; B) polysaccharides; D) all of the above. 10. Uracil forms a complementary bond with: A) adenine B) cytosine B) thymine D) guanine. 11. Glycolysis is called: A) the totality of all processes of energy metabolism in a cell; B) oxygen-free breakdown of glucose; B) complete breakdown of glucose; D) polymerization of glucose to form glycogen. 12. The order of the mitosis stage is as follows: A) metaphase, telophase, prophase, anaphase; B) prophase, metaphase, telophase, anaphase; B) prophase, metaphase, anaphase, telophase; D) telophase, prophase, metaphase, anaphase; 13. Chromosome duplication occurs in: A) interphase B) metaphase B) prophase D) telophase 14. In anaphase of mitosis, divergence occurs: A) daughter chromosomes B) non-homologous chromosomes B) homologous chromosomes D) cell organelles. 15. Of the animals listed, the largest egg is in: A) sturgeon B) lizard B) frog D) chicken. 16. The following are formed from the ectoderm: A) muscles B) skeleton B) lungs D) sensory organs. 17. In a Mendeleev monohybrid cross, the proportion of individuals with at least one recessive gene in the second generation will be equal to: A) 25% B) 50% C) 75% D) 100%

18. Genes located on: A) one chromosome B) sex chromosomes B) homologous chromosomes D) autosomes are called linked genes. 19. Mutations manifest themselves phenotypically: A) always B) only in a homozygous state B) only in a heterozygous state D) never. 20. Polyploidy consists of: A) a change in the number of individual chromosomes B) a change in the structure of chromosomes B) a multiple change in the haploid number of chromosomes; D) changes in the structure of individual genes. ANSWER: 1 – C, 2 – B, 3 – B, 4 – C, 5 – C, 6 – B, 7 – D, 8 – B, 9 – D, 10 – A, 11 – B, 12 – B, 13 – A, 14 – A, 15 – D, 16 – D, 17 – B, 18 – A, 19 – C, 20 – B. OPTION – 2 1. According to Charles Darwin, the driving forces of evolution are: A) struggle for existence; B) natural selection; B) hereditary variability; D) all of the above. 2. The leading role in evolution is played by the following type of variability: A) certain; B) group; B) modification; D) mutational. 3. The driving form of selection usually leads to: A) destruction of individuals with deviations B) expansion of the previous norm of reaction; from the previous norm of reaction; B) narrowing of the previous norm of reaction; D) a shift in the previous norm of reaction. 4. Similar organs are: A) gills of crayfish and gills of fish; C) birch leaves and cactus needles; B) a dog’s paw and a bird’s wing; D) all of the listed pairs. 5. During the Ice Age lived: A) Cro-Magnons; B) synanthropes; B) Neanderthals; D) all of the above. 6. The productivity of an ecosystem is called: A) its total biomass; B) total biomass of producers; B) the increase in this biomass per unit of time; D) total biomass of consumers. 7. Prokaryotic cells have: A) nuclei; B) mitochondria; B) ribosomes; D) all of the listed organelles. 8. Leukoplasts are cell organelles in which: A) protein synthesis occurs; C) there are red and yellow pigments; B) the process of photosynthesis is carried out; D) starch accumulates. 9. Nucleotides in a strand of a DNA molecule are connected by the following bond: A) covalent; B) peptide; B) hydrogen; D) disulfide bridges. 10. Transcription is: A) synthesis of an mRNA molecule B) delivery of amino acids to ribosomes along the matrix of one of the DNA chains; during protein synthesis; B) transfer of information from mRNA to protein D) process of assembly of a protein molecule. during its synthesis; 11. ATP synthesis in the cell occurs in the process of: A) glycolysis; B) cellular respiration; B) photosynthesis; D) all of the above. 12.The longest phase of mitosis is:

A) prophase; B) anaphase; B) metaphase; D) telophase. 13. Reduction in the number of chromosomes occurs during: A) anaphase of mitosis; B) II division of meiosis; B) I division of meiosis; D) in all of the above cases. 14. The biological significance of meiosis is to ensure: A) genetic stability; B) genetic variability; B) tissue regeneration and increase D) asexual reproduction. number of cells in the body; 15. The nervous system is formed from: A) ectoderm; B) mesoderm; B) endoderm; D) there is no correct answer. 16. The following are formed from the mesoderm: A) lungs; B) circulatory system; B) nervous system; D) sense organs. 17. How many types of gametes are formed by diheterozygous individuals: A) one; B) four; B) two; D) there is no correct answer. 18. Mutational variability includes: A) changes in chromosomes; B) changes that are inherited; B) changes in genes; D) all of the above. 19. The main source of combinative variability is: A) chromosome crossover B) independent chromatid divergence In prophase I of the meiotic division; in anaphase II of meiotic division; B) independent divergence D) all of the above processes to an equal extent. homologous chromosomes in anaphase I of meiotic division; 20. Interline hybridization of cultivated plants leads to: A) preservation of the same productivity; B) increasing productivity; B) the emergence of new characteristics; D) consolidation of signs. ANSWER: 1 - G, 2 - G, 3 - G, 4 - A, 5 - B, 6 - B, 7 - B, 8 - G, 9 - A, 10 - A, 11 - G, 12 - A, 13 – B, 14 – V, 15 – A, 16 – V, 17 – V, 18 – D, 19 – D, 20 – V.

The theory of evolution by C. Darwin and A. Wallace.

Key points:

1. All types of living organisms arose naturally.

2. Organisms slowly and gradually transformed and improved.

3. The basis for the transformation of species is variability, heredity and natural selection. Selection occurs through the interactions of organisms with each other and environmental factors. These interactions are called the struggle for existence.

4. Individuals that are most adapted to changing environmental conditions survive and produce full-fledged offspring.

Synthetic theory of evolution is a rethinking of a number of Darwinian provisions from the standpoint of genetics (S. Chetverikov, J. Haldane, N. Timofeev-Resovsky, R. Fisher). It is characterized as a theory of evolution occurring through natural selection of genetically determined traits.

Key points:

1. The elementary unit of evolution is the population.

2. The material for evolution is mutational and combinational variability.

3. Natural selection is seen as main reason development of adaptations, speciation and origin of supraspecific taxa.

4. A species is a group of populations that are reproductively isolated from populations of other species.

5. Speciation consists of the emergence of genetic isolating mechanisms and is carried out under conditions of geographic isolation.

The process of formation of new genera from species, from genera - families, from families - orders, etc. called macroevolution. Unlike microevolution, which occurs within a population, macroevolution is supraspecific and very long-term evolution.

Evidence of evolutionary processes is provided by paleontological, morphological, embryological and biochemical data.

There are three main directions of evolution.

Aromorphosis – evolutionary changes leading to a qualitatively new level of organization (multicellularity, central nervous system, photosynthesis). Thanks to aromorphosis, new large taxonomic units arise: types (divisions), classes.

Idiomatic adaptation – small evolutionary changes expressed in adaptation to the environment. In this case, the level of organization does not increase. Thanks to idioadaptation, small taxonomic groups are formed: species, genera, families.

Mutations constantly arise in populations under the influence of factors and cause changes in its gene pool. Population waves is a phenomenon of fluctuations in population numbers that are associated with periodic changes in the intensity of environmental factors (change of seasons, amount of precipitation, temperature fluctuations).

Insulation helps prevent individuals from different parts of the population from crossing with each other and leads to divergence of characteristics within the same species.

Geographical isolation leads to the rupture of a single habitat of a species into parts separated from each other and prevents interbreeding. The reasons for its appearance are the emergence of mountains, new rivers, straits, etc.

Environmental insulation based on differences in dispersal or timing of reproduction. For example, some species of salmon spawn every other year, and in the same rivers one population of fish spawns in one year and another in another.

Biological isolation associated with differences in the structure of the genital organs, mating songs, courtship rituals, secreted odors, etc.

The greatest importance in the evolutionary process is natural selection. It plays a creative role in nature, selecting from undirected hereditary changes only those that lead to the formation of new groups of individuals that will be more adapted to new environmental conditions.

Soviet biologist I.I. Schmalhausen developed (1946) the idea of ​​group selection - the survival of populations, species, genera, families, orders, etc. But because group selection occurs on the basis of the experiences of the organisms that make up these groups; individual natural selection also plays a leading role in evolution - the selection of the most adapted individuals.

Textbook for grades 10-11

Chapter XI. Mechanisms of the evolutionary process

Charles Darwin in his classic work “The Origin of Species” resolved the question of the main driving forces(factors) evolutionary process. He identified the following factors: heredity, variability, struggle for existence and natural selection. In addition, Darwin pointed out the important role of limiting the free crossing of individuals due to their isolation from each other, which arose in the process of evolutionary divergence of species.

Modern knowledge about evolution and its factors has developed into the so-called synthetic theory of evolution, which is the result of the development of Darwinism, genetics, ecology and other biological sciences.

Evolutionary theory proceeds from the fact that the elementary evolutionary unit, that is, the minimal cell that is capable of historical change (evolution), is a population.

§ 45. The role of variability in the evolutionary process

All individuals of the same species of animals and plants differ from each other to a greater or lesser extent. Variability of organisms - important factor the course of the evolutionary process.

Mutational variability. Mutational variability plays the role of the main provider of hereditary changes. It is this that is the primary material of all evolutionary transformations. One common type of genomic mutation is polyploidy, which is important in plant evolution. Polyploid plant species often occupy arctic and alpine zones. It is believed that this is due to their increased resistance to adverse environmental factors.

Chromosomal mutations also play an important evolutionary role. First of all, it is necessary to point out the duplication of genes on one chromosome. It is thanks to gene duplications that genetic material accumulates in the process of evolution. The increasing complexity of the organization of living things during historical development was largely based on an increase in the number genetic material. Suffice it to say that the amount of DNA in a cell in higher vertebrates is approximately 1000 times greater than in bacteria. Another type of chromosomal mutation, which is often found in animals and plants, is the movement of a section of a chromosome.

Individuals heterozygous for such mutations often have reduced fertility, while homozygotes reproduce normally. Some scientists believe that the appearance of such mutations can disrupt the genetic unity of a species and lead to isolation within its reproductively isolated populations.

SERGEY SERGEEVICH CHETVERIKOV (1882-1959) - domestic scientist, evolutionist and geneticist. His work gave rise to the modern synthesis of genetics and classical Darwinism.

The most common type of mutation is genetic. They play a very important role in the evolutionary process. Mutations of individual genes occur rarely. A gene mutation occurs on average in one in 100,000 gametes. But since the number of genes in an organism (for example, mammals) is about 40,000, almost every individual carries a newly emerged mutation. Most mutations are recessive; dominant mutations occur much less frequently. Dominant and recessive mutations behave differently in populations. Dominant mutations, even if they are in a heterozygous state, appear in the phenotypes of individuals already in the first generation and are subject to the action of natural selection. Recessive mutations appear in the phenotype only in the homozygous state.

A recessive mutation must accumulate in significant numbers in the population before it manifests itself in the homozygote phenotype. This idea was first expressed by the domestic geneticist S.S. Chetverikov. He was the first scientist to take the most important step towards combining genetics with evolutionary theory. In 1926 Chetverikov published famous work“On some aspects of the evolutionary process from the point of view of modern genetics,” with which it began new stage development of evolutionary theory.

S. S. Chetverikov made an important conclusion about the saturation of natural populations a large number recessive mutations. He wrote that a population, like a sponge, absorbs recessive mutations while remaining phenotypically homogeneous. The existence of such a hidden reserve of hereditary variability creates the opportunity for evolutionary transformations of populations under the influence of natural selection. As I.I. Shmalgauzen showed, the very ability of populations to accumulate genetic variability is the result of natural selection.

IN lately Thanks to the successes of molecular genetics and developmental genetics, it is becoming increasingly clear what a huge role mutations that arise not in the structural (protein-coding) genes themselves, but in the regulatory regions of these genes, play in evolution. They can modify the level of transcription of structural genes and the time and place of their switching on and off, creating a huge variety of forms and functions of organisms. Significant morphological differences between classes of vertebrates depend on the accumulation of small mutations in regulatory elements.

Let's look at a simple example. The size and position of the thorax in the chicken, mouse and boa constrictor are controlled by the same structural gene. The nucleotide sequence in this gene is the same in all three species (as in all other vertebrates). However, changes that have occurred in its regulatory elements lead to the fact that in a boa constrictor this gene operates in almost all cells of the embryo's notochord, in a mouse - in the anterior part, and in a chicken - in the posterior part of the notochord. As a result, the boa constrictor's chest is formed from the head almost to the tip of the tail, in a mouse - closer to the head, and in a chicken - closer to the tail.

Natural populations have accumulated huge number mutations in regulatory elements of a wide variety of structural genes.

Combinative variability. As you already know, combinative variability is a consequence of the crossing of homologous chromosomes, their random divergence in meiosis and the random combination of gametes during fertilization. Combinative variability leads to the emergence of an infinitely large variety of genotypes and phenotypes. It serves as an inexhaustible source of hereditary diversity of species and the basis for natural selection. If we assume that in each pair of homologous chromosomes there is only one pair of allelic genes, then for a person whose haploid set of chromosomes is 23, the number of possible gametes will be 2 23, and the number of possible genotypes will be 3 23. Such a huge number of genotypes is 20 times greater than the number of all people on Earth. However, in reality, homologous chromosomes differ in several genes and the phenomenon of crossover is not taken into account in the calculation. Therefore, the number of possible genotypes is expressed in an astronomical number and we can confidently say that the appearance of two identical people is almost impossible. Identical twins are an exception.

The enormous genotypic and, therefore, phenotypic diversity in natural populations is the initial evolutionary material, with which natural selection operates.

1. What type of variability, in your opinion, plays a leading role in evolution? Justify your answer.
2. Describe the role of variability in the evolutionary process.
3. How can we explain the phenotypic homogeneity of populations of the same species? Is it possible to say that the gene pools of populations of the same species are the same?
4. Which biological processes, occurring in the body, underlie combinative variability?