Which form of reproduction provides the best adaptability? Formation of germ cells. Meiosis. Review questions and assignments

Having worked through these topics, you should be able to:

1. Formulate in your own words the definitions: evolution, natural selection, struggle for existence, adaptation, rudiment, atavism, idioadaptation, biological progress and regression.
2. Briefly describe how a particular adaptation is preserved by selection. What role do genes play in this, genetic variability, gene frequency, natural selection.
3. Explain why selection does not produce a population of identical, perfectly adapted organisms.
4. Formulate what genetic drift is; give an example of a situation in which it plays an important role, and explain why its role is especially important in small populations.
5. Describe two ways species arise.
6. Compare natural and artificial selection.
7. Briefly list aromorphoses in the evolution of plants and vertebrates, idioadaptations in the evolution of birds and mammals, angiosperms.
8. Name the biological and social factors of anthropogenesis.
9. Compare the effectiveness of consuming plant and animal foods.
10. Briefly describe the features of the most ancient, ancient, fossil man, modern man.
11. Indicate the developmental features and similarities of human races.

Ivanova T.V., Kalinova G.S., Myagkova A.N. "General Biology". Moscow, "Enlightenment", 2000

• Topic 14. "Evolutionary teaching." §38, §41-43 pp. 105-108, pp.115-122
• Topic 15. "Adaptability of organisms. Speciation." §44-48 pp. 123-131
• Topic 16. "Evidence of evolution. Development of the organic world." §39-40 pp. 109-115, §49-55 pp. 135-160
• Topic 17. "The Origin of Man." §49-59 pp. 160-172

The textbook corresponds to the basic level of the Federal component of the state standard of general education in biology and is recommended by the Ministry of Education and Science of the Russian Federation.

The textbook is addressed to students in grades 10-11 and completes the line of N.I. Sonin. However, the peculiarities of the presentation of the material make it possible to use it at the final stage of studying biology after textbooks of all existing lines.

What is the importance of microbial selection for industry and agriculture?

Biotechnology is the use of organisms, biological systems or biological processes in industrial production. The term "biotechnology" has become widespread since the mid-70s. XX century, although since time immemorial mankind has used microorganisms in baking and winemaking, in the production of beer and in cheese making. Any production that is based on a biological process can be considered biotechnology. Genetic, chromosomal and cellular engineering, cloning of agricultural plants and animals are various aspects of biotechnology.

Biotechnology not only makes it possible to obtain products important for humans, such as antibiotics and growth hormone, ethyl alcohol and kefir, but also to create organisms with predetermined properties much faster than using traditional breeding methods. There are biotechnological processes for wastewater treatment, waste processing, removal of oil spills in water bodies, and production of fuel. These technologies are based on the characteristics of the life activity of certain microorganisms.

Emerging modern biotechnologies are changing our society, opening up new opportunities, but at the same time creating certain social and ethical problems.

Genetic Engineering. Convenient objects of biotechnology are microorganisms that have a relatively simply organized genome, a short life cycle and a wide variety of physiological and biochemical properties.

One of the causes of diabetes is a lack of insulin, a pancreatic hormone, in the body. Injections of insulin isolated from the pancreas of pigs and cattle save millions of lives, but lead to allergic reactions in some patients. The optimal solution would be to use human insulin. Using genetic engineering methods, the human insulin gene was inserted into the DNA of Escherichia coli. The bacterium began to actively synthesize insulin. In 1982, human insulin became the first pharmaceutical drug produced using genetic engineering methods.

Growth hormone is currently obtained in a similar way. A human gene embedded in the genome of bacteria provides the synthesis of a hormone, injections of which are used in the treatment of dwarfism and restore the growth of sick children to almost normal levels.

Just like in bacteria, using genetic engineering methods it is possible to change the hereditary material of eukaryotic organisms. Such genetically rearranged organisms are called transgenic or genetically modified organisms (GMOs).

In nature, there is a bacterium that produces a toxin that kills many harmful insects. The gene responsible for the synthesis of this toxin was isolated from the bacterial genome and inserted into the genome of cultivated plants. To date, pest-resistant varieties of corn, rice, potatoes and other agricultural plants have already been created. Growing such transgenic plants that do not require the use of pesticides has enormous advantages, because, firstly, pesticides kill not only harmful but also beneficial insects, and secondly, many pesticides accumulate in the environment and have a mutagenic effect on living organisms (Fig. 92).

Rice. 92. Countries growing transgenic plants. Almost the entire area sown with transgenic crops is occupied by genetically modified varieties of four plants: soybeans (62%), corn (24%), cotton (9%) and rapeseed (4%). Varieties of transgenic potatoes, tomatoes, rice, tobacco, beets and other crops have already been created

One of the first successful experiments on the creation of genetically modified animals was carried out on mice in whose genome the rat growth hormone gene was inserted. As a result, the transgenic mice grew much faster and ended up being twice the size of normal mice. If this experience had exclusively theoretical significance, then the experiments in Canada already had obvious practical application. Canadian scientists introduced a gene from another fish into the salmon's genetic material, which activated the growth hormone gene. This caused the salmon to grow 10 times faster and gain weight several times higher than normal.

Cloning. The creation of multiple genetic copies of one individual through asexual reproduction is called cloning. In a number of organisms, this process can occur naturally; remember vegetative propagation in plants and fragmentation in some animals (§). If a piece of a starfish’s ray is accidentally torn off, a new full-fledged organism is formed from it (Fig. 93). In vertebrates this process does not occur naturally.

The first successful animal cloning experiment was carried out by researcher Gurdon in the late 60s. XX century at Oxford University. The scientist transplanted a nucleus taken from an epithelial cell of the intestine of an albino frog into an unfertilized egg of an ordinary frog, whose nucleus had previously been destroyed. From such an egg, the scientist managed to grow a tadpole, which then turned into a frog, which was an exact copy of the albino frog. Thus, for the first time it was shown that the information contained in the nucleus of any cell is sufficient for the development of a full-fledged organism.

Subsequent research conducted in Scotland in 1996 led to the successful cloning of Dolly the sheep from the mother's mammary gland epithelial cell (Fig. 94).

Cloning appears to be a promising method in animal husbandry. For example, when breeding cattle, the following technique is used. At an early stage of development, when the cells of the embryo are not yet specialized, the embryo is divided into several parts. Each fragment placed in a foster (surrogate) mother can develop into a full-fledged calf. In this way, it is possible to create many identical copies of one animal with valuable qualities.

Rice. 93. Regeneration of a starfish from one ray

Rice. 94. Cloning Dolly the Sheep

For specific purposes, individual cells can also be cloned, creating tissue cultures that can grow indefinitely in suitable media. Cloned cells serve as a substitute for laboratory animals because they can be used to study the effects of various chemicals, such as drugs, on living organisms.

Plant cloning takes advantage of a unique feature of plant cells. In the early 60s. XX century it was shown for the first time that plant cells, even after reaching maturity and specialization, under suitable conditions are capable of giving rise to an entire plant (Fig. 95). Therefore, modern methods of cell engineering make it possible to select plants at the cellular level, i.e., select not adult plants that have certain properties, but cells from which full-fledged plants are then grown.

Rice. 95. Stages of plant cloning (using the example of carrots)

Ethical aspects of biotechnology development. The use of modern biotechnologies poses many serious questions to humanity. Could a gene embedded in transgenic tomato plants, when the fruit is eaten, migrate and be integrated into the genome of, for example, bacteria living in the human intestine? Could a transgenic crop plant that is resistant to herbicides, diseases, drought, and other stress factors, when cross-pollinated with related wild plants, transfer these same properties to weeds? Will this not result in “super weeds” that will very quickly colonize agricultural lands? Will giant salmon fry accidentally end up in the open sea, and will this upset the balance in the natural population? Is the body of transgenic animals able to withstand the load that arises in connection with the functioning of foreign genes? And does a person have the right to remake living organisms for his own good?

These and many other issues related to the creation of genetically modified organisms are widely discussed by experts and the public around the world. Special regulatory bodies and commissions created in all countries claim that, despite existing concerns, no harmful effects of GMOs on nature have been recorded.

In 1996, the Council of Europe adopted the Convention on Human Rights in the Use of Genomic Technologies in Medicine. The document focuses on the ethics of using such technologies. It is argued that no individual can be discriminated against based on information about the characteristics of his genome.

Introducing foreign genetic material into human cells can have negative consequences. Uncontrolled integration of foreign DNA into certain parts of the genome can lead to disruption of gene function. The risk of using gene therapy when working with germ cells is much higher than when using somatic cells. When genetic constructs are introduced into germ cells, an undesirable change in the genome of future generations may occur. Therefore, international documents from UNESCO, the Council of Europe, and the World Health Organization (WHO) emphasize that any change in the human genome can only be made on somatic cells.

But perhaps the most serious questions arise in connection with the theoretically possible human cloning. Research in the field of human cloning is today prohibited in all countries, primarily for ethical reasons. The formation of a person as an individual is based not only on heredity. It is determined by the family, social and cultural environment, therefore, with any cloning, it is impossible to recreate a personality, just as it is impossible to reproduce all those conditions of upbringing and training that formed the personality of its prototype (nucleus donor). All major religious denominations of the world condemn any interference in the process of human reproduction, insisting that conception and birth should occur naturally.

Animal cloning experiments have raised a number of serious questions for the scientific community, the solution of which will determine the further development of this field of science. Dolly the sheep was not the only clone obtained by Scottish scientists. There were several dozen clones, and only Dolly remained alive. In recent years, improvements in cloning techniques have allowed the percentage of surviving clones to increase, but their mortality rate is still very high. However, there is a problem that is even more serious from a scientific point of view. Despite Dolly's triumphant birth, her real biological age, associated health problems and relatively early death remained unclear. According to scientists, the use of a cell nucleus from a middle-aged six-year-old donor sheep affected the fate and health of Dolly.

It is necessary to significantly increase the viability of cloned organisms, to find out whether the use of specific techniques affects the life expectancy, health and fertility of animals. It is very important to minimize the risk of defective development of the reconstructed egg.

The active introduction of biotechnology into medicine and human genetics has led to the emergence of a special science - bioethics. Bioethics– the science of ethical attitude towards all living things, including humans. Ethics standards are now coming to the fore. Those moral commandments that humanity has used for centuries, unfortunately, do not provide for the new opportunities brought into life by modern science. Therefore, people need to discuss and adopt new laws that take into account the new realities of life.

Review questions and assignments

1. What is biotechnology?

2. What problems does genetic engineering solve? What are the challenges associated with research in this area?

3. Why do you think the selection of microorganisms is currently becoming of paramount importance?

4. Give examples of the industrial production and use of waste products of microorganisms.

5. What organisms are called transgenic?

6. What is the advantage of cloning over traditional breeding methods?

Issues for discussion

Chapter "Organism"

“The organism is a single whole. Diversity of organisms"

1. Why do you think science still does not know the exact number of species of organisms living on our planet?

2. In the cells of which organisms do special-purpose organelles exist? What functions do they perform?

3. Consider whether multicellular organisms may lack tissues and organs.

"Metabolism and energy conversion"

1. How are photosynthesis and the problem of providing food for the world's population related?

2. Explain why eating too much food leads to obesity.

3. Why can’t energy exchange exist without plastic exchange?

5. Give examples of the use of the metabolic features of living organisms in medicine, agriculture and other industries.

"Reproduction"

1. What do you think is the advantage of double fertilization in angiosperms compared to fertilization in gymnosperms?

2. Why is there no splitting of characteristics in the offspring of hybrids during vegetative propagation?

3. Think about the difference between natural vegetative propagation and artificial propagation.

4. The organism developed from an unfertilized egg. Are its hereditary characteristics an exact copy of the characteristics of the maternal organism?

5. Which form of reproduction do you think provides better adaptability to environmental changes?

"Individual development (ontogenesis)"

1. Why do different tissues and organs with different properties form from germ cells of equal value at the beginning of development?

2. What is the significance of development with transformation in adaptation to living conditions?

3. What significance did the extension of the pre-reproductive period have in human evolution?

4. For which organisms do the concepts “cell cycle” and “ontogenesis” coincide?

"Heredity and variability"

1. What is the advantage of diploidity over the haploid state?

2. Compose and solve problems for monohybrid and dihybrid crossing.

3. Mitochondria contain DNA, the genes of which encode the synthesis of many proteins necessary for the construction and functioning of these organelles. Consider how these extranuclear genes will be inherited.

4. Explain from the perspective of genetics why there are many more colorblind people among men than among women.

5. Do you think environmental factors can affect the development of an organism carrying a lethal mutation?

6. What experiment would you propose to set up to prove the genetic determination of behavioral reactions?

7. What do you think is the danger of consanguineous marriages?

8. Think about what is special about studying the inheritance of traits in humans.

9. Why does human economic activity increase the mutagenic influence of the environment?

10. Can combinative variability appear in the absence of the sexual process?

“Fundamentals of selection. Biotechnology"

1. What are the similarities and differences between the methods of plant and animal breeding?

2. Why do each region need its own varieties of plants and animals?

3. Of the wide variety of animal species living on Earth, humans have selected relatively few species for domestication. What do you think explains this?

4. Heterosis usually does not persist in subsequent generations and fades away. Why is this happening?

5. Do you think mass selection can be used when breeding animals? Prove your opinion.

6. What is the significance for plant breeding of knowledge of the centers of origin of cultivated plants?

7. What prospects for the development of the national economy does the use of transgenic animals offer?

8. Can modern humanity do without biotechnology?

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Reproduction is one of the fundamental properties of living organisms. It is a necessary condition for the existence and evolution of species.

1) Formulate a definition of the concept “reproduction”. What is the significance of this process?

Answer: Reproduction is the reproduction of one's own kind, ensuring the continued existence of the species. As a result of reproduction, the number of individuals of a certain species increases, continuity and continuity in the transmission of hereditary information is achieved.

2) Fill out the table "Main types of reproduction."

Answer:

Signs	Types of reproduction
	asexual	sexual
Number of parents	1	2
Features of the cells from which a new organism develops	They develop faster, increase their numbers, and settle in the territory	A unique set of properties, more adapted to life
The degree of similarity of new organisms to the parent (or parent)	Hereditary properties	Hereditary properties
Examples of organisms that are characterized by this type of reproduction	Single-celled organisms, fungi, bacteria	Plants, animals, humans
Practical and scientific significance	Reproduction of homogeneous offspring	Continuous change of generations

3) Fill in the blanks in the sentences.

• Answer: The very first cell that gives rise to a new one body during sexual reproduction is called gamete. It is formed as a result fertilization. The essence of fertilization is that fusion occurs female and male reproductive cells - is formed zygote.

4) Using the textbook text about gametes of different organisms, compare sperm and spermatozoa. Identify similarities and differences and formulate a conclusion.

Answer: Sperm develop in all angiosperms and gymnosperms, and sperm develop in algae, mosses, ferns, mosses, horsetails, in most animals, and in humans.

5) Fill out the table "Features of female and male gametes in mammals."

Answer:

6) Fill out the table "Methods of asexual reproduction."

Answer:

Methods of asexual reproduction	Peculiarities	Examples of organisms
Division and budding	Outgrowths are buds from which new individuals develop	Unicellular and multicellular organisms
Sporulation	Germination and formation of new organisms	Plants, mushrooms
Vegetative propagation	Reproduction by body fragments	Plants, some animals

7) Explain why in most unicellular and multicellular organisms asexual reproduction can alternate with sexual reproduction. Illustrate your answer with examples.

• Answer: Asexual reproduction occurs when the organism is in favorable conditions. For example, in some marine coelenterates, the sexual generation is represented by unicellular free-swimming jellyfish, and the asexual generation is represented by sessile polyps.

Target: expand and deepen knowledge about the reproduction of organisms; carry out intermediate control of knowledge on the topic: “Reproduction of organisms.”

Study the picture and answer the questions orally

1. What features of the sperm allow it to transmit hereditary information to the male body, ensure high mobility and penetration into the egg?
2. What structural features of the egg can provide
developing embryo with nutrients?
3. As a result of what processes is a haploid formed?
set of chromosomes in gametes?
4. As evidenced by the similarity of the processes of meiosis,
inherent in all animals and humans?
5. How do changes occur in genetic
material of new generations?
6. Which of the following statements are correct:

a – as a result of meiosis, haploid cells are always formed, and as a result of mitosis, diploid cells are always formed;
b – gametes are always haploid;
c – gametes can be diploid.

7. Which form of reproduction provides better adaptability to environmental changes?
8. What is conjugation of homologous chromosomes? When does it happen?
9. How do the processes of mitosis and meiosis occur during the alternation of sexual and asexual phases of plant reproduction?
10. The English scientist J. Gurdon transplanted a nucleus taken from a frog intestinal cell into an egg whose own nucleus had previously been destroyed by ultraviolet irradiation. A tadpole grew, and then a frog, identical to the individual from which the nucleus was taken. What does experience prove? What practical application can this experiment have?
11. How can you create any number of genetically identical copies of any valuable animal?
12. What biological process is associated with the growth of strawberry plants in forest clearings in groups - clumps?
13. What is the essence of the sexual process?
14. What is the name of the type of genetic regeneration in prokaryotes when two bacterial cells come into contact with each other using a cytoplasmic bridge along which the bacterial chromosome moves from the donor cell to the recipient cell?
15. Look at the drawing. Why did new species arise in the second case, but not in the first?

16. What benefits does the formation of a large number of spores give the body?
17. Compare the processes of budding and reproduction by cell division.
18. Calculate how many ancestors could have contributed to the heredity of each modern individual in the second, third, fourth, fifth, etc. previous generations. (The calculation is carried out using the formula 2n–1, where n is the total number of generations.)

Perform verification work on individual cards(Annex 1).
Submit your work to your teacher for review.

Final work for the first semester

in biology

Option 1

I. : homeostasis, prokaryotes, carbohydrates, dissimilation, crossing over.

II. .

1. What is the name of the process of self-duplication of a DNA molecule?

1. replication;

2. recombination;

3. renaturation.

1. metabolism

2. assimilation

3. anabolism

4. catabolism

3. During the process of photosynthesis:

1. oxygen is absorbed

2. carbon dioxide is released

3. oxygen is released

1. two nucleotides

2. one nucleotide

3. three nucleotides

5. The processes of anabolism do not include:

1. photosynthesis

2. breathing

3. protein synthesis

4. lipid synthesis

1.biosynthesis

2. broadcast

3. reduplication

4. transcription

7. Name the metabolic feature of some organisms, by the presence of which they are called heterotrophic:

1. synthesize organic substances from inorganic ones;

2. break down organic substances into inorganic ones;

3. synthesize new organic substances by transforming organic substances of other organisms.

8. The end products of the oxidation of organic substances are:

1. ATP and water;

2. water and carbon dioxide;

3. ATP and oxygen

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

1.excitation and inhibition;

2. plastic and energy metabolism;

3. growth and development;

10. Living systems are considered open because they:

11. In addition to plants, autotrophic organisms include:

1. mushrooms - saprotrophs;

2. bacteria of decay;

12. Mitosis is preceded by:

2. chromosome doubling;

13. Mitosis does not provide:

3. asexual reproduction.

14. Indicate the correct sequence of phases of mitosis:

15. In the results of meiosis, the number of chromosomes in the resulting cells:

1. doubles

2. remains the same

3. halved

4. triples.

1. plants;

2. bacteria;

3. animals;

4. mushrooms.

17. Name the type of cell division in which two daughter cells with the same hereditary information as in the mother cell are formed from one original eukaryotic cell.

1. amitosis;

2. mitosis;

3. meiosis;

4. sexual reproduction.

18. Which cell organelle is where chromosomes are stored?

1. core;

2. mitochondria;

3. chloroplast;

4. Golgi complex.

19. What is the name of a fertilized egg?

1. gamete

2. zygote

3. blastomere

20. Chemosynthetic bacteria in the ecosystem:

4. Which form of reproduction provides better adaptability to environmental changes?

in biology

Option 2

I. Define the following concepts: adaptation, cell theory, enzymes, autotrophs, meiosis

II. For each question, choose one correct answer.

1. A circular DNA molecule not associated with proteins is characteristic of cells:

1. plants;

2. mushrooms;

3. bacteria.

2. The combination of simple substances into complex ones is called:

1. metabolism

2. assimilation

3. anabolism

4. catabolism

3. During the process of photosynthesis:

1. oxygen is absorbed

2. carbon dioxide is released

3. oxygen is released

4. What is the name of the process of formation of a protein molecule in ribosomes from amino acids?

1. transcription

2. reduplication

3. broadcast

5. Each amino acid is encoded:

1. two nucleotides

2. one nucleotide

3. three nucleotides

6. Animals do not create organic substances from inorganic ones, therefore they are classified as:

1. autotrophs;

2. heterotrophs;

3. chemotrophs.

7. Living systems are considered open because they:

1. built from the same chemical elements as nonliving systems;

2. exchange matter, energy and information with the external environment;

3. have the ability to adapt.

8. Mitosis is preceded by:

1. disappearance of the nuclear membrane;

2. chromosome doubling;

3. formation of the spindle;

4. divergence of chromosomes to the poles of the cell.

9. A pair of homologous chromosomes in metaphase of mitosis contains a number of chromatids equal to:

1. 4

2. 2

3. 8

10. Mitosis does not provide:

1. maintaining a constant number of chromosomes for the species

2. genetic diversity of species

3. asexual reproduction.

11. Indicate the correct sequence of phases of mitosis:

1. metaphase, prophase, anaphase, telophase

2. anaphase, metaphase, prophase, telophase

3. prophase, metaphase, anaphase, telophase

4. telophase, anaphase, metaphase, prophase

12. Type of frog development:

1. straight;

2. indirect;

3. placental.

13. Catabolic processes include:

1. photosynthesis;

2. protein synthesis;

3. cellular respiration.

14. General biology studies:

1. general patterns of development and functioning of living systems;

2. unity of living and inanimate nature;

3. origin of species.

15. In animal cells, storage carbohydrate is:

1. cellulose;

2. glucose;

3. glycogen.

16. Human haploid cells contain 23 chromosomes. How many chromosomes are contained in somatic cells of the human body?

1. 23 chromosomes;

2. 46 chromosomes;

3. 69 chromosomes.

17. Pairs of concepts are opposite in meaning:

1. pinocytosis – endocytosis;

2. phagocytosis – exocytosis;

3. endocytosis – exocytosis.

18. Individual development of any organism from the moment of fertilizationuntil the end of life - this is

1. phylogenesis,

2 ontogeny,

3 parthenogenesis,

4 embryogenesis.

19. In animals, germ cells contain a set of chromosomes

1. equal to the mother cell

3. haploid

4. diploid

20. The initial stage of embryonic development is education

1. gamete

2. zygotes

3 gastrula

4. neurula

III. Please answer the following questions.

5. Why is there no splitting of characteristics in the offspring during vegetative propagation?

Final work for the first semester

in biology

Option 3

I. Define the following concepts: denaturation, biology, photosynthesis, interphase, sexual dimorphism

II. For each question, choose one correct answer.

1. Eukaryotic cells include the following cells:

1. mushrooms;

2. bacteria;

3. blue-green.

1. metabolism

2. dissimilation

3. anabolism

4. catabolism

1. photosynthesis

2. breathing

3. protein synthesis

4. lipid synthesis

4. Each amino acid is encoded:

1. two nucleotides

2. one nucleotide

3. three nucleotides

5. During the process of photosynthesis:

1. oxygen is absorbed

2. carbon dioxide is released

3. carbon dioxide is absorbed

6. The process of translating information from mRNA into protein is called:

1.biosynthesis

2. broadcast

3. reduplication

4. transcription

7. In the results of meiosis, the number of chromosomes in the resulting cells:

1. doubles

2. remains the same

3. halved

4. triples.

8. Homeostasis is:

2. metabolism

3. relative constancy of the internal environment of the body

9. Gastrulation is:

1. mitotic division of the zygote

2. formation of a two-layer (three-layer) embryo

3. development of individual organs.

10. What method of cell division occurs during the formation of germ cells in animals and plants:

1. mitosis

2. amitosis

3. meiosis.

4. budding.

11. Which cell organelle is where chromosomes are stored?

1. core;

2. mitochondria;

3. chloroplast;

4. Golgi complex.

12. What is the name of a fertilized egg?

1. gamete

2. zygote

3. blastomere

13. Name the stage of meiosis during which crossing over occurs in the cell - a crossover of homologous chromosomes, as a result of which these chromosomes exchange homologous regions:

1. prophase I

2. metaphase I

3. prophase II;

4. metaphase II.

14. Chemosynthetic bacteria in the ecosystem:

1. consume ready-made organic substances;

2. decompose organic substances into mineral ones;

3. decompose minerals;

4. create organic substances from inorganic ones.

1. plants;

2. bacteria;

3. animals;

4. mushrooms.

16. Parthenogenesis is:

1. reproduction by developing an adult from an unfertilized egg;

2. reproduction of hermaphrodites, which have both testes and ovaries;

3. reproduction by budding.

17. Blastulation is:

1. cell growth;

2. repeated fragmentation of the zygote;

3. cell division in half.

18. Animals do not create organic substances from inorganic ones, therefore they are classified as:

1. autotrophs;

2. heterotrophs;

3. chemotrophs.

1. metaphase, prophase, anaphase, telophase

2. anaphase, metaphase, prophase, telophase

3. prophase, metaphase, anaphase, telophase

4. telophase, anaphase, metaphase, prophase.

20. Homeostasis is:

1. protecting the body from antigens

2. metabolism

3. relative constancy of the internal environment of the body.

III. Please answer the following questions.

1. The solution to what problems of humanity depends on the level of biological knowledge?

2. Why can’t energy metabolism exist without plastic metabolism?

3. Predict what would happen if all bacteria on Earth disappeared.

4. What significance did development with transformation have in adapting to living conditions?

5. Why is there no splitting of characteristics in the offspring during vegetative propagation?

Final work for the first semester

in biology

Option 4

I. Define the following concepts: variability, hydrophilicity, eukaryotes, chromosome, ontogenesis.

II. For each question, choose one correct answer.

1. What type of cells does this characteristic belong to: there is a cell wall containing chitin, there is a central vacuole in the cytoplasm, there are no plastids:

1. plant cell;

2. animal cell;

3. mushroom cell.

2. The breakdown of complex substances into simple ones is called:

1. metabolism

2. dissimilation

3. anabolism

4. catabolism

3. The processes of anabolism do not include:

1. photosynthesis

2. breathing

3. protein synthesis

4. lipid synthesis

4. Each amino acid is encoded:

1. two nucleotides

2. one nucleotide

3. three nucleotides

5. Oxygen released during photosynthesis is formed during the breakdown of:

1. glucose

2. ATP

3. water

4. proteins

6. Pairs of concepts are opposite in meaning:

1. pinocytosis – endocytosis;

2. phagocytosis – exocytosis;

3. endocytosis – exocytosis.

7. In animals, germ cells contain a set of chromosomes

1. diploid

2. twice as much as in body cells

3. haploid

8. The initial stage of embryonic development is education

1. gamete

2. zygotes

3 gastrula

4. neurula

9. The similarity between mitosis and meiosis is manifested in

1. reduction division

2. conjugation of homologous chromosomes

3. arrangement of chromosomes along the equator of the cell

4. the presence of crossing over between homologous chromosomes

10. Each new cell comes from the same way

1. divisions

2 adaptations

3 mutations

4 modifications

11. At high magnification of the microscope, a cell is visible, in the center of which, in one plane, there are intensely colored structures - chromosomes, which look like hairpins, with their bent sections facing the middle of the cell and their free sections facing the periphery. This cell is in one of the phases of mitosis. Name this phase of mitosis:

1. prophase

2 anaphase

3 telophase

4 metaphase.

12. At what development level does the offspring resemble the adult organism?but differs from him in body size and proportions?

1. Direct

2. with transformation

3 with metamorphosis

4 embryonic.

13. Name the stage of embryonic development, which is a single layerThe embryo is shaped like a hollow ball.

1. gastrula

2 blastulas

3rd stage of zygote

4 morulas

14. Animals do not create organic substances from inorganic ones, therefore they are classified as:

1. autotrophs;

2. heterotrophs;

3. chemotrophs.

15. Living systems are considered open because they:

1. built from the same chemical elements as nonliving systems;

2. exchange matter, energy and information with the external environment;

3. have the ability to adapt.

16. In addition to plants, autotrophic organisms include:

1. mushrooms - saprotrophs;

2. bacteria of decay;

3. chemosynthetic bacteria;

17. Mitosis is preceded by:

1. disappearance of the nuclear membrane;

2. chromosome doubling;

3. formation of the spindle;

4. divergence of chromosomes to the poles of the cell.

18. A pair of homologous chromosomes in metaphase of mitosis contains a number of chromatids equal to:

1. 4

2. 2

3. 8

19. Indicate the correct sequence of phases of mitosis:

1. metaphase, prophase, anaphase, telophase

2. anaphase, metaphase, prophase, telophase

3. prophase, metaphase, anaphase, telophase

4. telophase, anaphase, metaphase, prophase

20. Catabolism processes include:

1. photosynthesis;

2. protein synthesis;

3. breathing.

III. Please answer the following questions.

1. Highlight the main features of the concept “biological system”.

2. What diseases can result from impaired conversion of carbohydrates in the human body?

3. Why do viral diseases become epidemics?

4. What significance did development with transformation have in adapting to living conditions?

5. Why is there no splitting of characteristics in the offspring during vegetative propagation?