Oxyphotobacteria. Real bacteria

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Part 1. The Kingdom of Bacteria

Subkingdom True bacteria

Sub-kingdom of Archaebacteria

Subkingdom of Oxyphotobacterium

Into the kingdom bacteria (from the Greek "bacterion" - stick) unite the most ancient inhabitants of our planet, which in everyday life are often called microbes. These organisms have a cellular structure, but their hereditary material is not separated from the cytoplasm by the membrane - in other words, they are devoid of a formed nucleus. Most of them are much larger than viruses in size. The kingdom of bacteria, on the basis of important features of life, and above all metabolism, scientists divide into three subkingdoms: Archaebacteria, Real bacteria and Oxyphotobacteria.

Science is engaged in the study of the structure and characteristics of the vital activity of microorganisms microbiology.

Subkingdom True bacteria

Let us consider the structural features of bacteria using the example of representatives of the subkingdom of Real bacteria.

These are very ancient organisms that appeared, apparently, more than 3 billion years ago. Bacteria are microscopically small, but their clusters (colonies) are often visible to the naked eye. According to the shape and characteristics of the association of cells into groups, several categories of real bacteria are distinguished. Cocchi have a spherical shape; diplococci consist of pairwise contiguous spherical cells; streptococci formed by cocci, brought together in the form of a chain; sarcins - clusters of cocci that look like dense packs; staphylococci - a complex of cocci in the form of a bunch of grapes. Bacillus, or sticks, - elongated bacteria; vibrios - arcuate curved bacteria, and spirilla - bacteria with an elongated, corkscrew-like crimped shape, etc.

On the surface of bacterial cells, there are often flagella - organelles of movement, with the help of which they move in a liquid medium. In their organization, they differ from flagella and cilia of plants and animals. Some bacteria move in a "reactive" way, releasing a portion of mucus into the environment. The cell wall of bacteria is built in a very peculiar way and includes compounds that are not found in plants, fungi and animals. Usually it is strong enough, its basis is a substance murein, which is a mixture of polysaccharides and proteins. The cell wall of many bacteria is covered with a layer of mucus on top. The cytoplasm is surrounded by a membrane that separates it from the inside of the cell wall.

Bacteria shape

Location of flagella in bacteria

There are few membranes in the cytoplasm of bacteria, and they are not independent structures, but invaginations of the outer cytoplasmic membrane. There are no organelles surrounded by a membrane (mitochondria and plastids) at all. Proteins are synthesized by ribosomes, which are smaller than those of eukaryotes. All enzymes that provide vital processes are scattered in the cytoplasm or attached to the inner surface of the cytoplasmic membrane.

Usually bacteria multiply by dividing in two. Initially, the cell lengthens, the ring chromosome is duplicated in it, a transverse constriction is gradually formed, and then the daughter cells diverge or remain connected into characteristic groups - chains, packages, etc.

Under unfavorable conditions, for example, when the temperature rises or dries up, many bacteria form disputes. In this case, a part of the cytoplasm containing hereditary material is secreted and covered with a thick multilayer capsule. The cell seems to dry up - the metabolic processes in it stop. The bacterial spores are very resistant; they can remain viable in a dry state for many years, and also survive in the body of a sick person, despite active antibiotic treatment. Bacterial spores are spread by wind and other routes. Once in favorable conditions, the spore is converted into an active bacterial cell.

Sporulation scheme

Reproduction of a bacterial cell by dividing in two

Autotrophic bacteria (from the Greek. "auto" - myself and "trophos" - I feed), which independently synthesize organic substances from inorganic ones, are few. Some of them are capable of chemosynthesis- the synthesis of organic substances that form their body from inorganic ones using the energy of oxidation of inorganic compounds. Others form organic molecules from inorganic ones in the process photosynthesis, using the energy of sunlight.

In relation to oxygen, bacteria are divided into aerobes (existing only in oxygen environment) and anaerobes (existing in an oxygen-free environment). In addition, groups of bacteria are known that live in both oxygenated and anoxic environments.

Pathogenic bacteria

Bacteria are extremely widespread in nature. They inhabit the soil playing role destroyers organic matter - the remains of dead animals and plants. By converting organic molecules into inorganic ones, bacteria thereby cleanse the planet's surface from decaying residues and return chemical elements to the biological cycle.

And the role of bacteria in human life is enormous. So, obtaining 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 processes of fermentation of food products are also associated with bacterial activity.

There are bacteria symbionts (from Latin "sim" - together, "bios" - life), which live in the organisms of plants and animals, bringing them certain benefits. For example, nodule bacteria, settling in the roots of some plants, they are able to assimilate gaseous nitrogen from the soil air, convert it into soluble compounds and thus supply these plants with the nitrogen necessary for their vital activity. When the plants die, they enrich the soil with nitrogen compounds, which would be impossible without the participation of such bacteria.

Known predatory bacteria that eat representatives of other types of prokaryotes.

The negative role of bacteria is also great. Various types of bacteria cause spoilage of food, releasing their metabolic products in them, which are toxic to humans. Most dangerous pathogenic (from the Greek "pathos" - disease and "genesis" - origin) bacteria are the source of various diseases of humans and animals, such as pneumonia, tuberculosis, tonsillitis, anthrax, salmonellosis, plague, cholera, etc. They affect bacteria and plants.

Symbiont bacteria form nodules on plant roots

The result of the activity of bacteria - wood destroyers

Sub-kingdom of Archaebacteria *

Archaebacteria (from the Greek "archios" - the most ancient), perhaps the oldest living prokaryotes, and therefore of all other living organisms; they appeared on our planet more than 3.8 billion years ago.

In total, a little more than 40 species of archaebacteria have been described. Some of them are capable of living in extreme conditions.

Among archaebacteria, the most famous methane-forming bacteria, which, as a result of metabolism, emit combustible gas methane. A significant part of the methane on Earth (10–15 × 10 6 tons annually) is formed only by this group of prokaryotes. Methane-forming archaebacteria live in strictly anaerobic conditions: in flooded soils, swamps, silt of reservoirs, treatment facilities, and ruminant rumen.

Another group of archaebacteria - the so-called halobacteria- organisms capable of growing at a very high salt concentration. They live in salt lakes.

Among archaebacteria there are those that oxidize sulfur and its inorganic compounds with the formation of sulfuric acid and therefore can cause the destruction of stone and concrete structures, corrosion of metals, etc.

Halobacteria

Halobacteria live in the salty sediments of the Dead Sea

Sulfur bacteria

Methane-forming archaebacteria live in swamps

Subkingdom of Oxyphotobacterium *

The subkingdom includes several groups of bacteria, in particular the department cyanobacteria, often called blue-green algae. They are very widespread throughout the world. About 2 thousand species of cyanobacteria are known. These are ancient organisms that arose about 3 billion years ago. It is assumed that changes in the composition of the Earth's ancient atmosphere and its enrichment with oxygen are associated with the photosynthetic activity of cyanobacteria.

Cyanobacterial cells, round, elliptical, cylindrical, barrel-shaped or otherwise, can remain solitary, unite in colonies, and form multicellular filaments. Often they secrete mucus in the form of a thick sheath, surrounded by a dense membrane in some forms. In some species, the filaments branch and in places form multi-row thalli. Filamentous forms of cyanobacteria, in addition to ordinary cells, are capable of assimilating nitrogen from atmospheric air, converting it into various soluble inorganic substances. These cells supply the other cells of the thread with nitrogen compounds. Cyanobacteria, unlike real bacteria, never have flagella. Cyanobacteria usually multiply by dividing the cell in two, they do not have a sexual process.

Different forms of cyanobacteria

Cyanobacteria and archaea in a hot spring

Cyanobacteria often cause water bloom in ponds

Cyanobacteria form green spots on stones

Most cyanobacteria are autotrophic organisms and can synthesize all cell substances using light energy. However, they are also capable of a mixed diet.

Cyanobacteria often enter into symbiosis with other organisms. And in symbiosis with fungi, they form organisms such as lichens.

Most species inhabit freshwater basins, few live in the seas. During mass reproduction, cyanobacteria often cause "blooming" of water in ponds, which adversely affects the life of the inhabitants of the reservoir, since many cyanobacteria in the process of their vital activity release toxic substances. In addition, due to the mass death of cyanobacteria, the water begins to rot, an unpleasant odor appears. You cannot drink water from such reservoirs. On land, cyanobacteria live in the soil, forming characteristic green blooms on rocks and tree bark.

Species of the genus Anabena are artificially bred in the tropics in rice fields to enrich the soil with nitrogen compounds. Due to the nitrogen-fixing properties of this bacterium, which lives in the cavities of the leaves of the aquatic Azolla fern, rice can grow for a long time in the same place without fertilization. Some cyanobacteria in the countries of the East are used for food.

Micrographs of various cyanobacteria

Questions and tasks

1. What are the structural features of a bacterial cell? What chemicals make up the body of bacteria?

2. Name the main forms of bacterial cells.

3. How do bacteria move?

4. Using the material from the textbook, draw up a table and enter into it the groups of bacteria and how they get energy.

5. Are there predators among bacteria?

6. What taxonomic group do archaebacteria form?

7. What organisms are called aerobes? Why? What are their differences from anaerobes?

8. List the structural features of cyanobacterial cells.

9. How do bacteria multiply?

10. Why do you think bacteria are considered the most ancient organisms?

11. Discuss in class how you can prevent bloom.

12. Make a detailed outline of the paragraph.

Work with computer

Please refer to the electronic attachment. Study the material and complete the proposed tasks.

1.http: //artsiz.ucoz.ua/publ/shkolnikam_na_zametku/prokarioty/2-1-0-1 (General characteristics of prokaryotes)

2.http: //www.worldofnature.ru/dia/?act=viewcat&cid=578 (Prokaryotes: information and illustrations)

Part 2. Kingdom of Mushrooms

Department of Chitridiomycot

Zygomycot Department

Basidiomycot Department

Group of imperfect mushrooms

Oomikot Division

Lichens group

Modern biologists classify fungi as an independent kingdom of organisms that differ significantly from plants and animals.

Science is studying the kingdom of mushrooms, which includes at least 100 thousand species mycology (from the Greek "mykos" - mushroom, "logos" - teaching).

Scientists believe that fungi are a composite group of organisms of different origins. It is possible that fungi are one of the first eukaryotes, but their early history is practically unknown. The vast majority of modern mushrooms live on land. However, the earliest mushrooms were obviously freshwater or marine organisms.

Fungi lack the pigment that provides photosynthesis, chlorophyll, and are heterotrophs. Some properties of mushrooms bring them closer to animals: they accumulate in cells as a reserve nutrient. glycogen, not starch like plants; the cell wall includes chitin, similar to arthropod chitin; as a product of nitrogen metabolism, they form urea. On the other hand, in terms of the way of feeding (by absorbing, not swallowing food), in terms of unlimited growth and immobility, they resemble plants.

A distinctive feature of fungi is the structure of their vegetative body. it mycelium, or mycelium, consisting of thin branching threadlike tubes - hypha.

Hat mushrooms

Mushrooms are diverse in structure and widespread in various habitats. Their sizes vary widely: from microscopically small (unicellular forms - yeast) to large specimens, the body of which reaches half a meter or more in diameter (these are, for example, large spherical raincoats, as well as edible mushrooms - white, boletus, etc.).

The mycelium, or mycelium, has a huge surface area through which it absorbs nutrients. The part of the mycelium located in the soil is called soil mycelium. The outer part - what we usually call a mushroom - also consists of hyphae, but very tightly intertwined. It - fruiting body mushroom. Reproductive organs are formed on it.

In most fungi, the mycelium is divided by septa into individual cells. The septa have pores through which the cytoplasm of neighboring cells communicates. Combining into bundles, hyphae form large cords, sometimes reaching several meters in length. Such strands perform, in particular, a conductive function. In some cases, dense interweaving of hyphae form thickenings rich in reserve nutrients, ensuring the survival of the fungus in unfavorable conditions, when the main part of the mycelium dies. Of these, mycelium develops again under conditions suitable for existence.

The structure of the fungus

A fungal cell usually has a well-defined cell wall. The cytoplasm contains a significant number of ribosomes and mitochondria, the Golgi apparatus is poorly developed. Protein granules can often be found in vacuoles. A large number of inclusions are represented by glycogen granules and fat droplets. The hereditary, or genetic, cell apparatus is concentrated in nuclei, the number of which ranges from one to several dozen.

Some unicellular fungi, such as yeast, have a body formed by a single budding cell. If the budding daughter cells do not diverge from each other, a mycelium is formed, consisting of several cells.

Mushrooms reproduce mainly asexually - disputes or vegetatively - with parts of the mycelium. Disputes develop on specialized hyphae - sporangiophores, rising above soil or other substrates. There is also sexual reproduction.

Mushroom Spore Cloud

Hyphae fungi in soil

Diagram of the structure of the fungus cell

A close connection is established between the roots of trees and the mycelium of some fungi, which is useful for both the fungus and the plant - a symbiosis arises. The filaments of the mycelium entwine the root and even penetrate inside it, forming mycorrhiza (from the Greek "mycos" - mushroom and "riza" - root). The mycelium absorbs water and dissolved minerals from the soil, which come from it to the roots of trees. Thus, mycelium can partially replace root hairs of trees. From the roots of the plant, the mycelium, in turn, receives the organic substances it needs for nutrition and the formation of fruit bodies.

In human economic activity, fungi play both a positive and a negative role. Yeast, which causes the fermentation process, is of great importance in the food industry. Many fungi form biologically active substances, enzymes, organic acids. They are used in the microbiological industry for the production of citric and other organic acids, as well as enzymes and vitamins. A number of species, such as ergot, chaga, are used as raw materials for the production of medicines.

Mushrooms are traditionally eaten. On the territory of our country, there are over 150 species of edible mushrooms, but only a few dozen are widely used.

Fungi are known - causative agents of human diseases, for example, mycosis of feet and hands, nails. Some fungi cause disease in domestic animals, harming livestock. An example of such a fungal disease is ringworm. Many fungi cause plant diseases - tinder fungi on trees, ergot in cereals, etc.

Sexual reproduction of basidiomycete fungi

Causative agents - chytridiomycot mushrooms

Sporangia with spores

In the kingdom of fungi, mycologists include several departments: Chytridiomycota, Zygomycota, Oomikota, Ascomycota and Basidiomycota. The largest of them are Ascomikota and Basidiomycota.

A separate group is formed by Imperfect mushrooms which reproduce only asexually or vegetatively and never form fruiting bodies.

Department of Chitridiomycot *

Zygomycot Department

Sawbol on manure

Mukor on bread

Mortirella

Department of Ascomycot, or Marsupial mushrooms

Ascomycota is one of the most extensive departments (about 30 thousand species). They got their name due to the formation of closed structures - bags (asok) containing spores. The department of Ascomikot includes, in particular, yeast, represented by single budding cells, numerous multicellular fungi with large fruiting bodies, for example morels and lines.

Ascomycot representatives are widespread in all natural zones and regions. According to the way of feeding, these are heterotrophs, they live in soil, forest litter, on various plant substrates and feed on decaying debris. Some species of ascomycot develop on substrates of animal origin, while others are involved in the decomposition of plant residues containing cellulose to inorganic molecules.

Many types of ascomycot form substances used in medicine for the treatment of infectious diseases (antibiotics), enzymes, organic acids and are used for their industrial production.

A group widely used by humans from the Ascomycot department is yeast. It is important to note that among yeast there are no species that form substances toxic to humans. When food deteriorates caused by yeast, the taste and appearance change, but harmful active substances do not accumulate, as is noted in poisonous fungi and bacteria. Baker's yeast only exists in culture. They are represented by hundreds of races: wine, bakery, beer and spirits.

Bag (asuka) with spores

Ergot cells contain highly toxic (poisonous) substances that can cause poisoning if they get into flour or animal feed. Ergot substances are widely used in modern medicine for the treatment of cardiovascular, nervous and other diseases. They are especially effective in obstetric and gynecological practice.

Some representatives of the ascomicote, such as morels and truffles, edible.

Ergot

Attention! This is an introductory excerpt from the book.

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The kingdom is one of the divisions of the classification of living organisms in nature from a scientific point of view. One of the five main kingdoms of living organisms is the kingdom of bacteria. Otherwise, they are called scraps.

This level of classification unites such subkingdoms as:

• bacteria.

The sub-kingdom of bacteria of the latter unites representatives of archaebacteria and. Bacteria are understood as the smallest prokaryotic organisms characterized by a cellular structure. are 0.1-30 microns, and it is impossible to see them visually. Today, about 2,500 have been studied in nature. Microbiology deals with the study of bacteria. She investigates representatives of the bacterial kingdom, which are not visible without special equipment (microorganisms):

• bacteria,
• microscopic fungi,
• seaweed.

Microbiology systematizes them into kingdoms, analyzes morphology, biochemistry, physiology, evolution and role in ecological systems.

A distinctive feature of the representatives of the bacterial kingdom is the absence of a nucleus surrounded by a membrane, separated from the cytoplasm. Some of them have, which makes them resistant to phagocytosis. Representatives of this kingdom are capable of reproduction every 20-30 minutes. Perhaps both sexually and by budding in some species. There are also species that are capable of sporulation (like mushrooms).

Classification of microorganisms

Depending on the shape of the bacterial cell, there are:

• (balls);
• (sticks);
• vibrios (curved by a boomerang);
• spirillae (spirals);
• (chain-like);
• (aciniform).

According to the method of assimilating nutrients from the surrounding nature, representatives of this kingdom are divided into the following groups:

In terms of the way of nutrition, bacteria are similar to fungi (saprotrophs, symbionts). Bacteria live in nature wherever there is at least some kind of organic matter: dust, water, soil, air, on animals, inside other living organisms. Their number grows every 20-30 minutes. In addition, there is another group of microscopic organisms that are. They are cyanobacteria. They are able to photosynthesize due to pigments similar in properties to those found in plants and algae. , thanks to the pigment, can be blue-green and green. They live colonially, filamentous formations and singly. Due to their similarity to algae, they can be symbiotic with fungi, forming a group of lichens. :

• obligate aerobes - live in conditions of free access of oxygen;
• obligate anaerobes - live in a complete absence of oxygen;
• facultative anaerobes - can exist under any conditions of oxygen access.

Functions of microorganisms in human life

They play a huge role, which is explained by the following facts:

1. by the process of their vital activity, they contribute to the formation of humus (organic fertilizer necessary for the life of plants).
2. Some microorganisms are capable of converting organic substances in nature into inorganic ones in a short time, which is especially important for.
3. In humans and animals, there are microorganisms involved in the process of digestion of the food consumed and the formation of vitamins.
4. Bacteria capable of causing are widely used for the production of alcohol, acetic acid, fermented milk products, silage.
5. Some bacteria can produce substances that can inhibit the vital activity of other living organisms, which has found its application in the production of antibiotics.
6. Synthesis of feed protein.
7. The participation of some bacteria in the synthesis of insulin, organic acids, alcohols, polymeric substances.
8. The ability of some microorganisms to cause death of the host.
9. Live bacteria are also used to make vaccines.

Negative effects of bacteria

In addition to all the listed positive properties of microorganisms, it should be mentioned that some bacteria can cause diseases. They are called

Real bacteria. Archaebacteria. Oxyphotobacterium

OPTION 1

In each task, choose one correct answer from the four suggested.

A1. All bacteria that inhabit planet Earth are united into a kingdom

1) Prokaryotes

3) Plants

4) Animals

A2. They do not have a formalized core

2) plants

3) bacteria

4) animals

AZ. The bacterial flagellum is an organoid for

1) movement

2) protein storage

3) reproduction

4) transferring unfavorable conditions

A4. Bacterial spores serve to

1) power supply

2) breathing

3) reproduction

4) transferring unfavorable conditions

A5. Organisms that feed on ready-made organic matter are called

2) autotrophs

3) anaerobes

4) heterotrophs

A6. Organisms that absorb oxygen during respiration are called

1) aerobes

2) anaerobes

3) autotrophs

4) heterotrophs

A7. Bacteria convert the remains of dead bodies of organisms into inorganic substances

1) destroyers

2) symbionts

3) nodule

4) pathogenic

A8 *... The way most cyanobacteria feed is

1) photosynthesis

2) fermentation

4) decay

A9 *. Methane-forming bacteria live in

1) swamps

2) salt lakes

3) plant roots

4) spring water

B1.

A. Chemosynthesis - the process of the formation of organic substances due to the energy of inorganic compounds.

B. Kefir is obtained using fermentation bacteria.

1) Only A is true

2) Only B is true

3) Both judgments are correct

4) Both judgments are wrong

B2. Pick three true statements. The bacterial cell includes

1) Decorated core

2) Chloroplast

3) Cytoplasm

4) Outer diaphragm

5) Mitochondria

6) Flagellum

B3. Establish a correspondence between the dietary habits and the ecological group of bacteria.

FEATURE FEATURES

A. They feed on the juices of living organisms, harming them

B. Themselves form organic matter due to the energy of sunlight

B. Carry out the transformation of organic substances of dead bodies into inorganic compounds

ECOLOGICAL GROUP OF BACTERIA

1) Destroyers

3) Autotrophs

IN 1.

Organisms that produce organic substances themselves are classified as ... (A), and organisms that absorb ready-made organic substances are ... (B). Of these, plant organisms, in which the primary source of energy is sunlight, are called ... (B).

Dictionary: 1. Phototrophs, 2. Autotrophs, 3. Heterotrophs

Answer: A-2, B-3, B-1

OPTION 2

A1. The most ancient inhabitants of our planet -

2) Plants

3) bacteria

4) Animals

A2. The hereditary cell material is not separated from the cytoplasm in

2) Plants

3) bacteria

4) Animals

AZ. Separates the bacterial cell from the environment

1) cytoplasm

3) nuclear envelope

4) outer membrane

A4. Bacterial cells multiply

1) disputes

2) flagella

3) areas of cytoplasm

4) cell division

A5. Organisms that are able to synthesize organic substances from inorganic compounds are called

2) anaerobes

3) autotrophs

4) heterotrophs

A6. Organisms that exist in an oxygen-free environment are called

2) anaerobes

3) autotrophs

4) heterotrophs

A7. Bacteria that interact with other organisms with mutual benefit are called

1) destroyers

2) symbionts

3) pathogenic

A8 *. The mutually beneficial relationship of cyanobacteria with fungi is called

1) symbiosis

3) predation

4) competition

A9 *. Halobacteria live in

1) swamps

2) salt lakes

3) plant roots

4) freshwater bodies

B1. Are the following statements true?

A. Photosynthesis is the process of formation of organic substances due to the energy of sunlight.

B. Disease-causing bacteria infect only the human body and are not found in the body of plants and animals.

1) Only A is true

3) Only B is true

4) Both judgments are correct

5) Both judgments are wrong

B2. Pick three true statements.

Bacteria carry out vital processes

1) cell division in half

2) reproduction by seeds

3) breathing

4) tissue formation

5) food

6) organ formation

BZ. Establish a correspondence between the eating habits of bacteria and the way they eat.

FEATURE FEATURES OF BACTERIA

A. Live in the bodies of other organisms and benefit them

B. eat other bacteria

C. Themselves form organic substances due to the energy of inorganic compounds

METHOD OF FOOD

1) Autotrophic

2) Symbiosis

3) Predation

Write down the corresponding numbers in the table.

IN 1. Read the text. Insert the numbers that indicate the words from the dictionary in the spaces of the gaps.

The content of the bacterial cell limits ... (A). The prokaryotic cell lacks ... (B). Bacteria that absorb oxygen during respiration are called ... (C), and those using other substances for oxidation are called ... (D).

Dictionary: 1. Anaerobes. 2. Plasma membrane. 3. Aerobes. 4. Nuclear shell.

Answer: A-2, B-4, B-3, G-1

First question Living organisms that have common characteristics are united into the kingdom of bacteria: 1 They consist of ... (one or many) cells 2 in a cell ... (present or absent) a well-defined nucleus 3 Very small organisms, visible ... (to the naked eye or only through a microscope) 4 Occur ... (in all or only in some) habitats Second question They are able to live both in the presence of oxygen (....... bacteria), and in an oxygen-free environment (.... . bacteria) Third question In industry, bacteria are used to obtain fermented milk products, for example ... Fourth question Most bacteria are heterotrophs, that is, they are used for nutrition .... Among them there are saprotrophs that use ...; bacteria settle in living organisms -... Fifth question Bacteria multiply by .... The high growth rate of bacteria is especially dangerous in the case of the multiplication of pathogenic bacteria, for example .... Sixth question Knowing about the existence of (invisible bacteria), it is important to observe the rules of hygiene: .... I give 60 points