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Prokaryotes. The kingdom of prokaryotes is the subkingdom of bacteria. bacteria are prokaryotes. These are the simplest, smallest and most widespread organisms that. Survival of bacteria during desiccation

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The structure of a bacterial cell has the following features:
there is no formed nucleus (the hereditary material (nucleoid) is not delimited from the cytoplasm by a membrane);
on the surface of cells there are often various kinds of flagella and villi - organelles of movement;
there is a cell wall, its basis is a substance close to cellulose, or fiber; many bacteria are covered on the outside with a layer of mucus;
there is a cytoplasmic membrane that separates the cytoplasm from the inside from the cell wall;
There are few membranes in the cytoplasm; they represent invaginations of the outer cytoplasmic membrane:
there are no organelles surrounded by a membrane (mitochondria, plastids, endoplasmic reticulum, Golgi apparatus, etc.);
ribosomes are smaller than those of eukaryotes;

enzymes that ensure vital processes are scattered in the cytoplasm or attached to the inner surface of the cytoplasmic membrane.

2. Name the main forms of bacterial cells.

Based on the shape and characteristics of the cell association, several groups of true bacteria are distinguished: cocci, spherical; diplococci, consisting of pairwise close cocci; streptococci, formed by cocci close together in the form of a chain, sarcina - cocci that look like dense packs; staphylococci - clusters of cocci in the form of a bunch of grapes; bacilli, or rods, are elongated bacteria: vibrios are arched bacteria; spirilla - bacteria with an elongated spur-like convoluted shape, etc.

3. How do bacteria travel?

Bacteria move using flagella and villi by gliding. Some, moving in a reactive manner, throw out mucus.

4. What groups are bacteria divided into based on methods of obtaining energy?

5. Are there predators among bacteria?

Yes. Predatory bacteria are known to eat representatives of other species of prokaryotes or unicellular eukaryotes.

6. What systematic group of prokaryotes do archaebacteria form?

Archaebacteria - the oldest living prokaryotes - form a sub-kingdom.

7. What organisms are called aerobes?

Aerobes are organisms that exist only in an oxygen environment and use oxygen for metabolic processes.

8. List the structural features of cyanobacterial cells.

Cyanobacterial cells, along with all the characteristics characteristic of a bacterial cell, have their own characteristic features:

contain pigments - chlorophylls, carotenoids, etc. (cyanobacteria are capable of photosynthesis);
in the cytoplasm there are gas pseudovacuoles, which give cyanobacteria a brown color;
mucus is often secreted onto the surface of the cell in the form of a thick sheath, surrounded in some forms by a dense membrane;
do not have flagella;
cells can remain single, unite in colonies and form multicellular filaments, and in some species the filaments branch and in some places form multirow thalli.

9. How do bacteria reproduce?

Bacteria usually reproduce by dividing in two. First, the doubling of the hereditary material—DNA—occurs; the cell elongates, a transverse partition gradually forms in it, and then the daughter cells disperse or remain connected in characteristic groups - chains, packets, etc.

10. What is the role of bacteria in nature?

Bacteria are very widespread in nature. They inhabit the soil, acting as destroyers of organic matter - the remains of dead animals and plants. Bacteria cleanse the surface of the planet from rotting residues, converting organic molecules into inorganic ones, thus returning chemical elements to the biological cycle. Nitrogen fixation is also important - binding nitrogen from the air and converting it into a form accessible for absorption by plants, which absolutely need nitrogen for life. For example, nodule bacteria that settle in the roots of leguminous plants have the ability to fix nitrogen.

11. What is the importance of bacteria in human life?

Bacteria play a huge role in human life. For example, the production of many food and technical products is impossible without the participation of various fermentation bacteria. As a result of the vital activity of bacteria, yogurt, kefir, cheese, koumiss, as well as enzymes, alcohols, and citric acid are obtained. The fermentation processes of food products are also associated with the activity of bacterial cells.

The negative role of bacteria is also great. Various types of bacteria cause food spoilage by releasing metabolic products that are toxic to humans. Cellulose-degrading bacteria spoil books and hay. The most dangerous pathogenic bacteria are the source of various diseases in humans and animals, such as pneumonia, tuberculosis, appendicitis, salmonellosis, plague, cholera, etc.

In a cage. Hereditary information is transmitted using circular DNA which is attached to the plasma membrane of the cell. In addition, prokaryotic cells contain ribosomes, and the cytoplasm has a gel consistency, which provides resistance to high temperatures. Prokaryotes reproduce through simple division, without the sexual process. Such organisms do not have multicellular forms.

The structure of a prokaryotic and eukaryotic cell. Differences in structure.

Kingdom of Drobyanka- this is the kingdom of living organisms, abolished today, which was previously called prokaryotes. The name is derived from the method of reproduction of prokaryotes - division. Prokaryotes appeared on earth more than 3.5 billion years ago.

Subkingdom Archaebacteria- these are the most ancient prokaryotes, which differ from other types of prokaryotes in structure and absence mureina(peptidoglycan) in bacterial cell walls. The circular DNA of archaebacteria is built according to the type of eukaryotic organisms - according to the type of redundant genome.

Archaebacteria are divided into three types:

1) Halobacteria;

2) Methanogenic bacteria;

3) Extreme thermophiles.

Halobacteria practice photosynthesis without the release of oxygen with the pigment bacteriorhodopsin.

Eubacteria- this is the largest group of microorganisms whose cell membrane contains murein. Are divided into gram negative bacteria And gram positive bacteria(determined using the reaction to aniline dyes). Eubacteria can form spores, and they reproduce using some kind of sexual process - conjugation, exchanging plasmids. Plasmids- These are small circular DNA, extrachromosomal particles that contain no more than one gene.

Based on the shape of the cells, the following types of eubacteria are distinguished:

Bacteria;
Cocci;
Vibrios;
bacilli;
Spirochetes;
Spirilla.

According to the type of nutrition, eubacteria are divided into photoautotrophs(without oxygen release), chemotrophs And heterotrophs. There are aerobic bacteria And anaerobic bacteria.

Eubacteria play an important role in the general biosystem:

1) Perform a geological role ( iron bacteria, sulfur bacteria and etc.);

2) Take a direct part in the cycle of substances ( saprotrophs);

3) They are causative agents of various diseases in other living organisms, including humans;

4) They are used by humans for their own purposes - in winemaking, cheese making, the formation of amino acids, feed protein, vitamins, etc.

Subkingdom Oxyphotobacteria. This sub-kingdom is divided into two divisions: chloroxybacteria and cyanobacteria(blue-green algae). Chloroxybacteria include prokaryotes of the genus Prochlorone, which were discovered in the second half of the 20th century. Scientists are still debating their origin. They live in symbiosis with ascidians in the seas of the tropics and subtropics. Their set of photosynthetic elements is the same as that of green algae and higher plants.

Bacteria are prokaryotes. These are the simplest, smallest and most widespread organisms that have existed on earth for more than 2 billion years, but at the same time constantly evolving. Bacteria are so different from other living organisms that they are classified as a separate kingdom. There are not many places in the world that are free of bacteria. They live in water, soil, air, inside and on the surface of the bodies of animals and plants.

GROUPS OF TRUE BACTERIA § cocci (spherical) - single § diplococci (collected in twos) § streptococci (in the form of a chain)

§ staphylococci (in the form of a bunch of grapes) § sarcina (in the form of dense packs) § bacilli (rod-shaped)

According to the method of nutrition, bacteria are divided into two groups: HETEROTROPHES AUTOTROPHES (they are not able to synthesize organic matter, but feed on ready-made ones) (able to synthesize organic substances from inorganic ones)

Most bacteria can use almost any organic compound as an energy source, even substances used to destroy them (for example, penicillin, which kills many bacteria). This is due to the fact that bacteria can live both in the presence of oxygen in the environment and in its absence.

Bacteria are divided into two groups according to their feeding method: Aerobic (during the process of respiration they use oxygen to oxidize organic substances) Anaerobic (decompose organic substances without the participation of oxygen)

In relation to the development temperature, bacteria are also very diverse: some develop over a wide range of temperature changes, others - only at certain temperatures (low, high or in a narrow temperature range).

REPRODUCTION OF BACTERIA Bacterial cells, under favorable conditions, multiply very quickly, dividing in two. If a cell doubles every half hour, then it can produce 281474976710656 offspring per day. And some bacteria can multiply even faster.

The rapid proliferation of lactic acid bacteria in milk causes it to turn sour in a matter of hours.

Formation of spores Under unfavorable conditions, for example, lack of water, many bacteria go into a dormant state. The cell loses water, shrinks somewhat and remains dormant until water appears again. Some species survive periods of drought, heat or cold in the form of spores. The formation of spores in bacteria is not a method of reproduction, since each cell produces only one spore and the total number of individuals does not increase.

When a spore forms, the cell shrinks, rounds within the existing cell wall and produces a new thick wall inside the old one. Under favorable conditions (humid conditions), the spore germinates. The spores are very resistant: they can withstand prolonged drying, boiling for several hours, and dry heating up to 140 o. C. Some spores can withstand temperatures of -245 o. C. They are also resistant to the action of toxic substances and remain viable for a long time. Thus, anthrax bacilli remain viable, remaining in the form of spores for 30 years.

Survival of bacteria during drying Vibrio cholera up to 2 days Plague bacillus up to 8 days Diphtheria bacillus up to 30 days Typhoid bacillus up to 70 days Tuberculosis bacillus up to 90 days Staphylococcus bacillus up to 90 days

The positive significance of bacteria is determined by their participation in many biological processes, especially in the cycle of substances in nature. Bacteria, as a result of their vital activity, are able to decompose complex organic compounds into simple inorganic substances, which are again used by green plants. Bacteria are capable of decomposing proteins, carbohydrates, and fats.

A number of substances produced by bacteria as a result of metabolism are very valuable for humans. The activity of bacteria is used in various industries and agriculture for the production of lactic acid products, for sauerkraut, forage silage, for the production of organic acids, alcohols, acetone, enzymatic preparations, etc.

Currently, bacteria are becoming extremely important as producers of many biologically active substances (antibiotics, amino acids, vitamins, etc.) used in medicine, veterinary medicine and animal husbandry. Without the participation of bacteria, the processes that occur during the preparation of leather for tanning, maceration of flax and hemp fibers are impossible.

People also use bacteria to treat wastewater: when wastewater is slowly passed over gravel and sand, solid particles settle and, under the influence of various bacteria, are transformed into a material that, after drying, is used as fertilizer. When passing through sand and gravel, pathogenic bacteria die and are digested by putrefactive bacteria.

Negative role of bacteria Pathogenic bacteria that cause diseases of plants, animals and humans play a negative role. Many saprophytic bacteria cause food spoilage, some of which are highly toxic. Toxins usually do not affect the body as a whole, but a specific organ or one of the organ systems - for example, the central nervous system, red blood cells, etc., causing a characteristic set of symptoms by which the disease can be diagnosed and its causative agent can be identified.

Of the plant diseases caused by bacteria, the following are known: burn that affects fruit plants - apple trees, pears, etc.; black rot of cabbage; soft rot of many plants; tumors of plant roots Despite the harm caused (bacterial root cancer); tumor-like growths on leaves (galls), etc.

SUB-KINGDOM REAL BACTERIA. SUBKINGDOM ARCHAEBACTERIA. SUBKINGDOM OXYPHOTOBACTERIA

Fill in the missing word.

1. Complete the sentences by inserting the necessary words.

A. With the help of flagella

B. “Reactive” - throwing out mucus

B. Using wings

D. All statements are true

9. Establish the sequence of processes during bacterial reproduction.

A. Formation of daughter cells

B. The cell elongates

B. A transverse constriction is formed

D. Duplication of the bacterial chromosome
10. Establish the sequence of processes during sporulation.

A. Stopping metabolism in the cell

B. Separation of part of the cytoplasm containing hereditary material

B. Formation of a thick multilayer capsule

D. The cell becomes smaller in size
11. Bacterial spores are...

A. Sex cell

B. Propagation form

B. Form for the survival of bacteria in adverse conditions

D. Name of bacteria
12. To obtain energy, bacteria use:

A. Organic compounds

B. Inorganic compounds

B. Sunlight

D. All statements are true
Find a match.

13. Select the appropriate characteristics for bacteria of different types of nutrition:

I. Heterotrophs

II. Autotrophs of chemosynthesis

III. Autotrophs of photosynthesis

A. Formation of organic substances from inorganic ones due to the energy of sunlight

B. They feed on ready-made organic substances

B. Formation of organic substances from inorganic substances due to the energy of oxidation of inorganic substances

14. From the proposed terms, create a diagram of the biological cycle:

I. Organic matter

II. Inorganic substances

III. Alive organisms

IV. Dead parts of living organisms and remains

V. Destroyer bacteria

Draw a conclusion about the role of destructive bacteria in the biological cycle.
15. Complete and draw up a diagram “The role of bacteria in human life.”

Using the diagram, write a story about the role of bacteria in human life.

16. Using the proposed terms, fill out the diagram:

I. Sulfur bacteria

II. Methanobacteria

III. Swamps, sewage treatment plants, animal rumen

IV. Methane gas

V. Sulfur and sulfur compounds

VI. Sulfuric acid

VII. Sulfur deposits

VIII. Archaebacteria
Using the diagram, prepare a story about the importance of archaeobacteria in nature.

17. Find the mistake in the sentence.

Based on their shape, bacteria are divided into cocci, bacilli, spirilla, thalli, and vibrios.
Choose the correct statement.

18. 1. Bacteria - diplococci are clusters of dense packs.

2. Flagella and villi are often developed on the surface of bacteria.

3. The cell wall of bacteria is formed by cellulose.

D. Availability of glycogen

E. Nutrition by suction
3. Mushrooms reproduce:

A. Vegetatively

B. Disputes

B. Seeds

G. Sexually
4. In mushrooms, spores develop in:

A. Gifah

B. sporangia

G. Mykorize
5. Fill in the missing word.

A. Symbiosis occurs between... and...

B. Mycelium replaces trees...
6. Mycorrhiza is:

A. Name of the mushroom

B. Mushroom root

B. A variety of mycelium

G. Dispute
7. Establish the sequence of processes during fungal propagation:

A. Germination of spores

B. Cell division

B. Spore maturation

D. Formation of the fruiting body

D. Formation of hyphae

E. Mycelium formation
8. From the listed terms, make a diagram of the supply of water and nutrients using the signs?, =

A. Hyphae

B. Mycelium

G. Fruiting body
9. The survival of the fungus in unfavorable conditions is ensured by:

A. The supply of nutrients is deposited in the cells of the thickened parts of the mycelium

B. A spore is formed

B. A large amount of water is stored

D. Metabolic processes slow down
10. The class Basidiomycetes includes:

A. Russula

B. Tinder

B. Zvezdovik

G. Potato mushroom
11. What fungus affects cereal crops and can cause human poisoning if it gets into flour?

A. Ergot

B. Penicill

B. Late blight

G. Yeast
12. Forms mold on food products:

A. Mukor

B. Penicill

B. Ergot

G. Phytophthora
Fill in the missing word.

13. The mycelium located in the soil is called..., the outer part of the mycelium is...

14. Pseudomycelium is formed from... as a result of...
15. Find the error in the statement.

A fungal cell has a cell wall, cytoplasm, nucleus, mitochondria, chloroplasts, ribosomes, endoplasmic reticulum, poorly developed Golgi apparatus, and vacuoles.

16. From the proposed terms, reflect schematically the phenomenon of “symbiosis”, using arrows to show the relationship:

I. Mycelium

III. Water and minerals

IV. Organic matter

V. Tree roots

17. In the diagram “Mushrooms in human economic life,” fill in the gaps, choosing the necessary words according to their meaning.
Using the diagram, prepare a story about the role of mushrooms in human economic activity.
Find a match.

18. What signs are characteristic of class mushrooms:

I. Chytridiomycetes

II. Zygomycetes

III. Ascomycetes, or marsupial fungi

IV. Basidiomycetes

D. Fruiting body in the form of bags containing spores, some of the representatives are single budding cells

19. 1. The kingdom of mushrooms includes at least 100 thousand species.

2. Cap mushrooms contain pigment.

3. Fungal cells contain a storage substance - glycogen.

4. Mycelium, or mycelium, consists of thin branching threads - hyphae.

5. Unicellular fungi - yeast.

A. Along the lower cortex

B. At the core

B. Between the core and the lower cortex

D. Between the core and the upper cortical layer
10. Lichens are attached to the ground using:

A. Rizoidov

B. Rhizoids and hyphae

D. Special adhesive substance
11. Lichens are found in:

A. Cold regions of the Earth

B. Temperate latitudes

B. Gorah

D. All statements are true
Choose the correct statement.

12. 1. Lichens are a group of symbiotic organisms.

2. Two components of lichens: an algae - a heterotrophic organism and a fungus - an autotrophic organism.

3. Each type of lichen is characterized by a certain fungus and algae.

4. Crustose lichens are the most complex.

5. The thallus of many lichens has lower and upper cortical layers of tightly woven fungal threads.

6. The core of lichens is formed by fungal threads and algae.

7. The fungus provides the alga with water and dissolved organic matter.

8. Lichen is characterized by new biological qualities that are not characteristic of algae and fungi outside of symbiosis.

9. Lichens grow on soil, rocky outcrops, trees and are demanding of clean air.

10. Lichens are resistant to low temperatures, lack of moisture and low levels of carbon dioxide in the atmosphere.

11. Lichens reproduce by parts of the thallus, i.e. vegetatively.

12. Lichens can reproduce by spores that are formed sexually and asexually.

13. Lichens accumulate solar energy, transform organic substances into inorganic ones, and transform rocks into soil suitable for plant growth.

Bacteria are divided into two groups according to their feeding method: Anaerobic (decompose organic substances without the participation of oxygen) Anaerobic (decompose organic substances without the participation of oxygen) Aerobic (in the process of respiration they use oxygen to oxidize organic substances) Aerobic (in the process of respiration they use oxygen to oxidize organic substances)

REPRODUCTION OF BACTERIA Bacterial cells, under favorable conditions, multiply very quickly, dividing in two. If a cell doubles every half hour, then within 24 hours it can produce offspring. And some bacteria can multiply even faster.

When a spore forms, the cell shrinks, rounds within the existing cell wall and produces a new thick wall inside the old one. Under favorable conditions (humid conditions), the spore germinates. The spores are very resistant: they can withstand prolonged drying, boiling for several hours, and dry heating up to 140oC. Some spores can withstand temperatures of -245oC. They are also resistant to toxic substances and remain viable for a long time. Thus, anthrax bacilli remain viable, remaining in the form of spores for 30 years.