Bacteria- one of the oldest organisms on Earth. Not respecting the simplicity of their life, the stench lives on in all possible children. The greatest number of them are found in soil (up to several billions of bacterial cells per 1 gram of soil). There are a lot of bacteria in the air, water, grub products, in the middle of the body and on the bodies of living organisms. Bacteria were found in places where other organisms cannot live (on ice fields, volcanoes).
Call a bacterium - not one cell (although there are colonial forms). Moreover, this cell is even smaller (ranging from a few microns to several tens of microns). The main feature of the bacterial cell is the cell nucleus. In other words, bacteria lie prokaryotes.
Bacteria come in different forms and in different forms. In some indestructible forms, drying occurs with the help of flagella. There may be several of them, or there may be just one.
Cells of different types of bacteria can vary greatly in form. Bacteria flourish ( coki), stick-like ( bacilli), similar to whom ( vibrations), zvivisti ( spirochetes, spirili) and in.
Budova bacterial culture
Cells are rich in bacteria mucus capsule. Vaughn has a dry function. Zokrema, protects the cell from drying out.
Just like in bacterial cells, there are climax wall. However, on the other hand, the chemical warehouse will be much different. The cell wall is made up of balls of folded carbohydrates. It is such that it allows various substances to penetrate into the middle of the body.
Under the wall of the wall cytoplasmic membranenA.
Bacteria are transferred to prokaryotes, since in their cells there is no formed nucleus. The stench does not stain the chromosomes characteristic of eukaryotic cells. The chromosome structure contains both DNA and proteins. In bacteria, their chromosome consists of DNA and a circular molecule. This genetic apparatus of bacteria is called nucleoid. The nucleoid is located directly near the cytoplasm, i.e. at the center of the cell.
Bacteria lack essential mitochondria and a number of other cellular organelles (Golgi complex, endoplasmic junction). Their functions involve the invagination of the cell cytoplasmic membrane. This is what we call mesosomes.
The cytoplasm has ribosomes, as well as various organic inclusion: proteins, carbohydrates (glycogen), fats. Bacterial cells can also cause damage pigments. Depending on the presence of these or other pigments or their content, the bacteria may appear clear, green, or purple.
Bacteria food
Bacteria emerged at the dawn of the formation of life on Earth. The stench itself was reeked of various methods of eating. Only then, from the complicated organisms, two great kingdoms were clearly visible: Rosliny and Creatures. The stinks tease each other about the method of eating. Roslins are autotrophs, and creatures are heterotrophs. Bacteria develop insults and food problems.
Harvesting is a way of removing essential organic substances from the body and the body. They can be separated out or synthesized independently from inorganic speeches.
Autotrophic bacteria
Autotrophic bacteria synthesize organic compounds from inorganic ones. The synthesis process requires energy. It is also important that autotrophic bacteria collect this energy and divide it into photosynthetic and chemosynthetic ones.
Photosynthetic bacteria vikorist energy of the Sun, catching his vibration. Whose stench is like roses. However, while plants exhibit sourness during the process of photosynthesis, most photosynthetic bacteria are not visible. Bacterial photosynthesis is anaerobic. Also, the green pigment of bacteria develops into a similar one to the growth pigment and is called bacteriochlorophyll. Bacteria do not have chloroplasts. Basically, photosynthetic bacteria hang around in water bodies (fresh and salt water).
Chemosynthetic bacteria For the synthesis of organic compounds from inorganic compounds, the energy of various chemical reactions is used. Energy is not visible in all reactions, but even more so in exothermic ones. Such reactions occur in bacterial cells. So do Nitrifying bacteria the oxidation reaction of ammonia in nitrite and nitrate takes place. Zalizobacteria oxidize the oxide in the oxide. Water bacteria oxidize water molecules.
Heterotrophic bacteria
Heterotrophic bacteria cannot synthesize organic compounds from inorganic ones. Therefore, it is difficult to remove them from the excessive middle ground.
Bacteria that live on organic residues of other organisms (including dead bodies) are called saprophytic bacteria. They are also called rot bacteria. There are a lot of such bacteria in the soil, where they decompose humus into inorganic liquids, which are easily grown by vicor. Lactic acid bacteria eat carcasses, converting them into lactic acid. Butyric acid bacteria decompose organic acids into carbohydrates and alcohols into olic acid.
Bulbyak bacteria live in root weeds and feed on the organic matter of living weeds. However, the stench binds nitrogen from the soil and protects the growth from it. This is where symbiosis occurs. Other heterotrophic symbiotic bacteria they hesitate in the herbal apparatus of the creatures, helping to poison the hedgehogs.
In the process of breathing there is a ruination of organic speeches from liberated energies. This energy is wasted in various processes of life (for example, on the planet).
An effective way to retain energy is through sour breathing. However, some bacteria can produce energy without acid. Thus, there are aerobic and anaerobic bacteria.
Aerobic bacteria necessary sourness, so the stinks linger in places, de vin. Kisen takes part in the reaction of oxidation of organic substances to carbon dioxide and water. During this process, bacteria retain a very large amount of energy. This method of breathing is characteristic of an important number of organisms.
Anaerobic bacteria If you don’t require sourness for cooking, you can linger in the sour-free medium. The energy of the stench is captured by the rahunok fermentation reactions. This oxidation method is ineffective.
Reproduction of bacteria
Most often, bacteria reproduce by dividing their cells in two. Before this, the sub-warning of the circular DNA molecule occurs. The skin daughter cell contains one of these molecules and, therefore, a genetic copy of the mother cell (clone). In this manner, it is typical for bacteria without article reproduction.
In agreeable minds (for a sufficient number of living speeches and agreeable minds of too much middle age), bacterial cells multiply even rapidly. Thus, one bacteria can produce hundreds of millions of cells per bite.
If bacteria multiply in an unstated way, in a number of outbreaks they are wary of such names article process what is happening in the form conjugation. During conjugation, two different bacterial cells come close, and a bond is established between them by the cytoplasm. Parts of the DNA of one cell are passed on to each other, and parts of the DNA of another cell are passed on to each other. Thus, during the genetic process, bacteria exchange genetic information. Sometimes bacteria exchange not pieces of DNA, but entire DNA molecules.
Superchicks of bacteria
What is important is the large number of bacteria in hostile minds to create superfluids. Supercells of bacteria - what is important is the way of surviving hostile minds and the method of dispersal, and what is not the method of reproduction.
When the supercell is closed, the cytoplasm of the bacterial cell is compressed, and the cell itself is covered with a thick, thick dry coating.
The microbes of bacteria maintain vitality for long periods of time and even survive even unfavorable conditions (extremely high and low temperatures, drying out).
If the superechka is consumed by a friendly mind, it will swell. After this, the dry membrane is shed and the original bacterial cell appears. It happens that in this case the underclothes are exposed and a bunch of bacteria are created. Then the spore creation will grow from reproduction.
Significance of bacteria
The role of bacteria in the circulation of water in nature is significant. We are immediately confronted with rotting bacteria (saprophytes). They call them nature's orderlies. By decomposing the excess of plants and animals, bacteria convert complex organic substances into simply inorganic ones (carbon dioxide, water, ammonia, hydrochloric acid).
Bacteria increase the fertilization of the soil, rich in nitrogen. In nitrifying bacteria, reactions occur in which nitrites are created from ammonia, and nitrates are created from nitrites. Bulbyak bacteria acquire atmospheric nitrogen, synthesizing nitrogenous compounds. It stinks to live near the root growths, the soothing bulblets. These bacteria of the plant produce the nitrogenous substances they need. Basically, legume plants enter into symbiosis with bulbulococci bacteria. After drying, the soil becomes rich in nitrogen. This is often the case with the rural dominion.
In the mouth of chewing animals, bacteria form cellulose, which causes effective etching.
The role of bacteria in the food industry is very positive. Numerous species of bacteria are used for the extraction of lactic acid products, butter and syrup, fermented vegetables, and also in wine production.
In the chemical industry, bacteria are used to produce alcohols, acetone, and otic acid.
In medicine, such bacteria are eliminated with low antibiotics, enzymes, hormones and vitamins.
However, bacteria can cause illness and harm. The smells don’t just eat food products, but spoil them with their visions.
The structural components of the cell are the membrane of bacteria, which consists of the cell wall, cytoplasmic membrane and capsule; cytoplasm; ribosomes; various cytoplasmic inclusions; nucleoid (nucleus). Several types of bacteria are present, including superechella, flagella, viii (pili, fimbriae) (Fig. 2).
Cliff wall obligatory formation of bacteria of most species. They will be stored due to their belongings
bacteria to groups that differentiate under the hour of storage using the Gram method. The mass of the cell wall should be approximately 20% of the dry mass of the cell wall, thickness – from 15 to 80 nm.
Small 3. Scheme of biological bacterial cells
1 – capsule; 2 – climax wall; 3 – cytoplasmic membrane; 4 – cytoplasm; 5 – mesosomes; 6 – ribosomes; 7 – nucleoid; 8 – internal cytoplasmic membrane structures; 9 – fat spots; 10 - polysaccharide granules; 11 - polyphosphate granules; 12 - switch on; 13 - flagella; 14 - basal body
The cell wall has pores with a diameter of up to 1 nm, so it is a permeable membrane through which living substances penetrate and metabolic products are visible.
These substances can penetrate the internal microbial tissue only after a preliminary hydrolytic cleavage by specific enzymes, which are present in bacteria in the external core.
The chemical composition of the cell wall is heterogeneous, but is stable for the most common type of bacteria, which is determined by identification. The cell wall contains nitrogenous compounds, lipids, cellulose, polysaccharides, and pectin.
The most important chemical component of the cell wall is a foldable polysaccharide peptide. It is also called peptidoglycan, glycopeptide, murein (from the Latin. murus - Stenka).
Murein is a structural polymer that is composed of glycan molecules formed by acetylglucosamine and acetylmuramic acid. The synthesis of yogurt in the cytoplasm is limited to the level of the cytoplasmic membrane.
The peptidoglycan of the cell wall of various species has a specific amino acid composition and, therefore, a distinct chemotype that is useful when identifying lactic acid and other bacteria.
At the cell site of gram-negative bacteria, peptidoglycan is represented by one ball, while at the station of gram-positive bacteria, the veins form a bunch of balls.
In 1884 Gram introduced the method of tissue preparation, which was used for the preparation of prokaryotic cells. If, when preparing a gram of fixed protein, treat the crystalline violet farbi with alcohol, and then with iodine, then this mixture creates a stable preparation complex with murein.
In positive microorganisms of fertilization, the violet complex is not dissolved when injected with ethanol and is apparently not spoiled; when supplemented with fuchsin (red color farb), the cells are deprived of fermentation in dark violet color
In gram-negative species of microorganisms, gentian violet is dissolved by ethanol and washed away with water, and when prepared with fuchsin, the cletin is barred in red color.
The data of microorganisms are prepared by analyte barnacles and called the Gram method tinctorial authorities . They need to be inoculated in young (18-24 year old) cultures, because some gram-positive bacteria in older cultures can be positively infected by the Gram method.
The importance of peptidoglycan is due to the fact that the cell wall is always rigid. springiness and dry framework of the bacterial cell.
When peptidoglycan is damaged, for example, under the influence of lysozyme, the cell wall loses rigidity and collapses. Instead, tissue (cytoplasm) immediately swells from the cytoplasmic membrane into a spherical shape, thus becoming a protoplast (spheroplast).
A large number of synthesizing and waste enzymes are associated with the cell wall. The components of the cell wall are synthesized at the cytoplasmic membrane, and then transported to the cell wall.
Cytoplasmic membrane It expands under the wall and fits tightly to its inner surface. It is a membrane that contains the cytoplasm and the inner part of the cell - the protoplast. The cytoplasmic membrane is the outer thickened ball of cytoplasm.
The cytoplasmic membrane is the main barrier between the cytoplasm and the extra core, the destruction of which leads to the death of the cell. This warehouse includes proteins (50-75%), lipids (15-45%), and in many species – carbohydrates (1-19%).
The main lipid component of the membrane is phospho-glycolipids.
The cytoplasmic membrane, with the help of enzymes localized in it, performs various functions: synthesizes membrane lipids - components of the cell wall; membrane enzymes – selectively transfer various organic and inorganic molecules and ions through the membrane, the membrane takes part in the transformation of cellular energy, as well as in the replication of chromosomes, in the transferred electrochemical energy and electrons.
Thus, the cytoplasmic membrane ensures the selective passage of the cell and the removal of various substances and ions from it.
Similar to the cytoplasmic membrane mesosome . These are spherical structures that are formed when the membrane is twisted at the curl. The stench arises from both sides - at the site of creation of the cellular septum or from the zone of localization of nuclear DNA.
Mesosomes are functionally equivalent to the mitochondria of cells in other organisms. They take part in the oxidative reactions of bacteria, play an important role in the synthesis of organic substances, and in the formation of the cell wall.
Capsule This is similar to the outer ball of the mucous membrane, which drains one or a few microbial cells. Its thickness can reach 10 microns, which often exceeds the thickness of the bacteria itself.
The capsule loses its function. Chemical warehouse of bacteria capsules is different. In most cases, it is composed of folding polysaccharides, mucopolysaccharides, and some polypeptides.
Capsule creation, as a rule, has a specific sign. However, the appearance of microcapsules often lies behind the cultivation of bacteria.
Cytoplasm- Collapsible colloidal system with a large amount of water (80-85%), in which proteins, carbohydrates, lipids, as well as minerals and other substances are dispersed.
Cytoplasm is, instead of tissue, a cytoplasmic membrane. It is divided into two functional parts.
One part of the cytoplasm is in the form of sol (dilution), has a homogeneous structure and contains a set of different ribonucleic acids, enzyme proteins and metabolic products.
Another part is represented by ribosomes, inclusions of various chemical natures, genetic apparatus, and other internal cytoplasmic structures.
Ribosomes– these are submicroscopic granules containing spherical nucleoprotein particles with a diameter of 10 to 20 nm, a molecular weight of about 2-4 million.
Ribosomes of prokaryotes are composed of 60% RNA (ribonucleic acid), which is located in the center, and 40 % protein that covers the nucleic acid of the ring.
Inclusion of cytoplasm exchange products, as well as reserve products, for which products live in the minds of not enough living people.
The genetic material of prokaryotes consists of a suspended strand of deoxyribonucleic acid (DNA) of a compact structure, spread out in the central part of the cytoplasm and not reinforced by a membrane. The DNA of bacteria is not differentiated from the DNA of eukaryotes, unless it is reinforced by a cytoplasmic membrane, the genetic material is called nucleoid or else genophore. The nuclear structures are spherical and horseshoe-shaped.
Argue A bacterium is a form that rests and does not reproduce. The smells are formed in the middle of the plate, into round or oval shapes. Spores are created mainly by gram-positive bacteria, rod-like forms with aerobic and anaerobic types of death in old cultures, as well as in the unfriendly minds of the modern environment (few living organisms and vologists, accumulation of metabolic products in the environment, changes in pH and cultivation temperature, visibility or presence may switch to an alternative development program, the result will be super-scores. With this, one superchka is created in the client. It is worth mentioning that spore formation in bacteria is used to preserve the species (individual) and is not the method of their reproduction. The process of spore formation occurs, as a rule, in the middle age, lasting 18-24 years.
A mature chick becomes approximately 0.1 volume of the mother's cell. The superstructures of various bacteria vary according to their shape, size, and distribution of tissue.
Microorganisms in which the diameter of the superechina does not exceed the width of the vegetative tissue are called bacilli, the bacteria that form supers, whose diameter is 1.5-2 times larger than the cross-section of the body, are called clostridia.
In the middle of the microbial cell, spores can grow in the middle of the central position, at the end of the terminal position, and between the center and the end of the cell in subterminal position.
Jugella bacteria and locomotor organs (organs of motion), where bacteria can be transferred at a speed of up to 50-60 µm/s. In this case, for one bacteria, they cover the balance of your body by 50-100 times. The doubling of flagella outweighs the doubling of bacteria in 5-6 times. The thickness of the flagella is on average 12-30 nm.
The number of flagella, their size and distribution are constant for different types of prokaryotes and therefore must be taken into account when identifying them.
Depending on the number and locality of flagella, bacteria are divided into monotrichs (monopolar monotrichs) - clitins with one flagellum at one end, lophotrichs (monopolar polytrichs) - a bunch of flagella Roztashov Present at one end, amphitrichous (bipolar polytrichous) – flagella grow on the skin at the poles , peritrichs - flagella spread over the entire surface of the cell (Fig. 4) and atriches - bacteria, reduced flagella.
The nature of the bacteria depends on the number of flagella, bacteria, culture characteristics, temperature, the presence of various chemicals and other factors. Monotrichs are the most fragile.
Flagella are more common in rod-like bacteria; they do not live on the necessary cell structures, so there are non-flagellate variants of loose types of bacteria.
The main features of the prokaryotic (bacterial) cell and the eukaryotic cell are the presence of a formed nucleus (the nuclear membrane), the presence of internal cell membranes, nuclei, the Golgi complex, lysosomes, etc. Itochondria.
The main structures of bacterial cells are:
Nucleoid – condensed (genetic) material of bacterial cells, represented by 1 DNA molecule, closed in a ring and supercoiled (twisted into a fluffy ball). The DNA depth is close to 1mm. The amount of information is about 1000 gens (signs). The nucleoid is not bound to the cytoplasmic membrane.
Cytoplasm is a colloid, that is. water distribution of proteins, carbohydrates. Lipids, mineral compounds, which contain ribosomes, inclusions, plasmids.
Protein biosynthesis occurs on ribosomes. Prokaryotic ribosomes differ from eukaryotic ones to smaller sizes (70 S).
Inclusions include reserves of living bacterial cells, as well as the accumulation of pigments. Add the following to the remaining living ingredients: granules of volutin (inorganic polyphosphate), glycogen, granulose, starch, drops of fat, pigment, syrup, calcium. Inclusion occurs when bacteria grow on rich living media and occurs during fasting.
The cell membrane encloses the cytoplasm. Consists of a secondary globule of phospholipids and produced membrane proteins. KM, in addition to the barrier and transport functions, plays a role in the center of metabolic activity (as opposed to eukaryotic cells). Membrane proteins responsible for transporting essential substances to cells are called permeases. On the inner surface of the CM there are enzyme ensembles, which are an ordering of enzyme molecules responsible for the synthesis of energy carriers - ATP molecules. CM can be embedded in the cytoplasm, called mesosomes. There are two types of mesosomes:
Septals - create transverse partitions at the bottom of the wall.
Lateral – serve to increase the surface of the CM and increase the fluidity of exchange processes.
Nucleoid, CP and CM create protoplast.
One of the significant effects of bacteria is a very high internal osmotic pressure (from 5 to 20 atm), which is the result of an intense metabolism of molecules. Therefore, to protect against osmotic shock, the bacterial cell is sharpened by the cell wall.
Behind the wall of the cell, all bacteria are divided into two groups: Single-ball cell wall - Gram-positive. Those who wash the double-walled wall - Gram-negative. Call Gram+ and Gram create your own history. In 1884, the Danish microbiologist Hans Christian Gram developed an original method of fermenting microbes, as a result of which some bacteria were barked in a blue color (gram+), and others in a red color (gram-). The chemical basis of various bacterial inoculations using the Gram method was recently discovered - about 35 years ago, there is a stench. It turned out that G- and G+ bacteria are present throughout the tissue wall. Budova of the cell wall of G+ bacteria. The basis of the cell wall of G+ bacteria is composed of 2 polymers: peptidoglycan and teichoic acids. Peptidoglycan is a linear polymer that contains excess muramic acid and acetylglucosamine. A tetrapeptide (protein) is covalently bound to muramic acid. Threads of peptidoglycan are connected to each other through peptides and form the cellular framework - the basis of the clinal wall. Between the threads of peptidoglycan there is another polymer - teichoic acids (glycerol TC and ribitol TC) - a polymer of polyphosphates. Teichoic acids appear on the surface of the cell wall and head AG G+ bacteria. Moreover, Mg ribonucleate enters the cell wall of G+ bacteria. The wall of G-bacteria consists of 2 balls: the inner ball represents a mono- or bilayer of peptidoglycan (thin ball). The outer sphere is made up of lipopolysaccharides, lipoproteins, proteins, phospholipids. LPS of all G-bacteria are toxic and have a threshold level of power and are called endotoxins.
When taking certain drugs, such as penicillin, the synthesis of the peptidoglycan ball is disrupted. In this case, the protoplast is created with G+ bacteria, and the protoplast with G-spheroplast (the outer ball of the cell wall is saved in fragments).
In the old minds, the cultivation of cells, the removal of the cell wall, preserves the size until the growth of the floor, and such forms are called L-forms (under the name of the Lister Institute, which was clearly a phenomenon). In some cases, after subtraction of the factor that stimulates the synthesis of the cell wall, the L-form can be converted to output forms.
Most bacteria synthesize mucus, which is composed of mucopolysaccharides, which is deposited from the outer side of the cell wall, secreting the bacterial cell into the mucus sheath. This is a capsule. The function of the capsule is to protect bacteria from phasocytosis.
Superficial structures of bacterial cells.
Organs of attachment to the substrate (adhesion) – pili (fimbriae) and vii. They begin at the cell membrane. Folded from a protein sheet. The number of files can be up to 400 per 1 clinic.
Organs of transmission of spasmodic information – F-drank and sex-drank. F-drinks are only approved in this case, since the cell is not a plasmid, because F-pili proteins are encoded by plasmid DNA. The stench is a thin, long tube that attaches to other bacterial cells. Through the channel, once created, the plasmid passes to the bacterial cell.
Organs of the ruhu - flagella - are spiral threads. Their diameter can be increased by 10 or more times. The flagellum is formed from the protein flagellin. The base of the flagellum is connected to the cell membrane near the basal body. The basal body is composed of a system of rings that wrap around to transmit the involucral structure to the flagellum. After growth by the flagellum, bacteria are divided into mono-, lopho-, amphi-, and peritrichous.
Bacteria are microscopic single-celled organisms. Everyday bacterial cell has its own peculiarities, which is the reason why bacteria are seen in the surrounding kingdom of the living world.
Obolonki klitini
Most bacteria contain three membranes:
- cliniform membrane;
- clitar wall;
- mucus capsule.
In the middle, instead of the cell membrane, the cell membrane adheres to the cytoplasm. That's tonka ta m'yaka.
The wall of the wall is thick and thick. Its function is protection and support of the client. The cell wall and membrane have pores through which the necessary words enter the cell.
A lot of bacteria coat the mucus capsule, which reduces the drying function and ensures stickiness to different surfaces.
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The very mucous membrane of streptococci (one of the types of bacteria) sticks to the teeth and causes caries.
Cytoplasm
Cytoplasm is the internal part of the cell. Composed of 75% water. The cytoplasm contains inclusions - some fat and glycogen. The stench is from the spare living substances of the cell.
Small 1. Scheme of biological bacterial cells.
Nucleoid
Nucleoid means “similar to a nucleus.” Bacteria do not have a proper, or, as it seems, formed, nucleus. This means that they do not have a nuclear envelope or nuclear space, like the cells of fungi, plants and creatures. DNA is found in the cytoplasm.
Functions of DNA:
- saves emergency information;
- implements this information through the synthesis of protein molecules attached to this type of bacteria.
The presence of the true nucleus is the most important feature of bacterial cells.
Organoids
In the presence of cells and animals, bacteria do not destroy organoids formed from membranes.
In some places, the cellular membrane of bacteria penetrates into the cytoplasm, creating folds called mesosomes. The mesosome takes part in the reproduction of cells and exchanges energy and replaces membrane organelles.
The only organelle that bacteria have is the ribosome. These small bodies, located near the cytoplasm, synthesize proteins.
Many bacteria have a flagellum, which causes the stench to move into the rare media.
Forms of bacterial cells
The shape of bacterial cells varies. Bacteria such as coules are called coca. In appearance, the coma has vibrions. Rod-like bacteria – bacilli. Spirals have the appearance of a wilted line.
Small 2. Form bacteria bacteria.
Bacteria can only be observed under a microscope. The average cell size is 1-10 microns. Plantweed bacteria grow smaller to 100 microns. (1 µm = 0.001 mm).
Sporulation
When hostile minds arise, the bacterial cell transforms into a hibernating cell, which is called a spore. The causes of spore formation may be:
- decrease and increase in temperature;
- dry land;
- nonstacha food;
- The life of the speech is not safe.
The transition takes place quickly, lasting 18-20 years, and the cell can last hundreds of years. With the restoration of normal minds, the bacterium germinates in 4-5 years from superstructures and enters a normal mode of life.
Small 3. Scheme of superechka creation.
Reproduction
Bacteria multiply underground. The period from the breeding of a plant to its growth becomes 20-30 years. That's why bacteria spread across the Earth.
What did we find out?
We found out that bacteria, similar to plants and animals, stink the membrane, cytoplasm, and DNA. The main feature of bacterial cells is the presence of a formed nucleus. Therefore, bacteria are called prenuclear organisms (prokaryotes).
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To identify bacterial cells using a light microscope, electron microscopic and microchemical studies are carried out to determine the ultrastructure of bacterial cells.
Bacterial cellin (Fig. 5) is composed of the following parts: trispheral membrane, cytoplasm with various inclusions and nuclear molecule (nucleoid). Additional structural solutions include capsules, supercapsules, flagella, files.
Small 5. Schematic representation of a bacterial cell. 1 – shell; 2 – slime ball; 3 – climax wall; 4 – cytoplasmic membrane; 5 – cytoplasm; 6 – ribosome; 7 – polysome; 8 – switched on; 9 – nucleoid; 10 - flagellum; 11 - drank
Obolonka The cell consists of the outer mucus ball, the cell wall and the cytoplasmic membrane.
The mucous capsular ball is involved in the tissue and has a dry function.
The wall of the cell is one of the main structural elements of the cell, which preserves its shape and strengthens the cell from the extra middle. The important power of the cell wall is vibrational penetration, which ensures the penetration of necessary living substances (amino acids, carbohydrates, etc.) into the cell and the removal of metabolic products from the cell. The client wall maintains a constant osmotic pressure in the middle of the client. The integrity of the wall is ensured by murein, a substance of polysaccharide nature. Some words build up the wall of the body, for example, lysozyme.
Bacteria that contain only the cell wall are called protoplasts. The stench preserves its properties until death, fermentation, and enzyme synthesis; before the influx of external factors: mechanical damage, osmotic pressure, aeration, etc. Protoplasty can be preserved only in hypertonic conditions.
Bacteria with a partially structured cell wall are called spheroplasts. As soon as the process of cell wall synthesis is suppressed with the help of penicillin, L-forms are created, which in all types of bacteria are clusters of large and small cells with vacuoles.
The cytoplasmic membrane closely adheres to the cell wall from the inner side. It is thinner (8-10 nm) and consists of proteins and phospholipids. This is a borderline penetrating ball, through which the life of the body is created. The membrane contains permease enzymes, which are active in the transfer of substances, and dihanna enzymes. The cytoplasmic membrane creates mesosomes, which take their part from the cell line. When a hypertensive disorder is placed on the client's wall, the membrane may become embedded in the client's wall.
Cytoplasm- Internal instead of bacterial cells. It is a colloidal system, which consists of water, proteins, carbohydrates, lipids, and various mineral salts. The chemical composition and consistency of cytoplasms change continuously with the age of the culture and the minds of the middle class. The cytoplasm contains nuclear membranes, ribosomes and various inclusions.
Nucleoid, nuclear speech of the cell, її spasmodic apparatus. The nuclear fluid of prokaryotes, unlike eukaryotes, does not contain a moisture membrane. The nucleoid of a mature cell consists of a double strand of DNA, folded in a circle. The DNA molecule encodes the genetic information of the cell. In genetic terminology, nuclear speech is called a genophore or genome.
Ribosomes are found in the cytoplasm of cells and play a role in protein synthesis. The ribosomes contain 60% RNA and 40% protein. The number of ribosomes in a cell reaches 10,000. By joining together, ribosomes create polysomes.
Included are granules that contain various reserve substances: starch, glycogen, fat, volutin. The stench is dissolved in the cytoplasm.
Bacterial cells in the process of life create dry organelles – capsules and superstructures.
Capsule- External thickening of the mucus ball, which adjoins the cliniform wall. This is a chemical organ that appears in certain bacteria when they enter the body of humans and animals. The capsule protects the microorganism from harmful factors in the body (causes of pneumonia and anthrax). Several microorganisms form a permanent capsule (klebsii).
Argue are especially common in rod-like bacteria. The stench is created when the microorganism enters the hostile mind (high temperatures, drying, pH change, change in the amount of living fluids in the middle, etc.). Spores are found in the middle of the bacterial cell and represent a thickened section of cytoplasm with a nucleoid, encased in a thick, thick membrane. Behind the chemical warehouse, stinks are eliminated from vegetative cells with a small amount of water, a large mixture of lipids and calcium salts, which absorbs the high resistance of spores. Sporulation lasts for 18-20 years; When contacted by a microorganism in a friendly mind, the superchids sprout in a vegetative form over a period of 4-5 years. Bacterial cells develop only one cell, and super cells are reproductive organs, and serve to survive hostile minds.
Spore-forming aerobic bacteria are called bacilli, and anaerobic bacteria are called clostridia.
Controversy arises over the shape, size and arrangement of the cloth. The stench can develop centrally, subterminally and terminally (Fig. 6). In the spore plant, the spore grows centrally, and its size does not exceed the diameter of the cell. The spore of the botulism organism grows closer to the end of the cell - subterminal and exceeds the width of the cell. At the zbudnik, the right rounded superchoke expands at the end of the wedge - terminally and significantly outweighs the width of the wedge.
Jugella- organs characteristic of rod-like bacteria. These are thin thread-like fibrils that form a protein called flagellin. The dovzhina significantly outweighs the dovzhina of bacterial cells. The flagella emerge from the basal body, disseminated in the cytoplasm, and emerge on the surface of the cell. Their presence can be detected by the marked friability of cells under a microscope, in rare veins, or when prepared using special methods. The ultrastructure of flagella was examined under an electron microscope. After growth of flagella, bacteria are divided into groups (div. Fig. 6): monotrichs - with one flagellum (cholera); amphitrichous - with bundles and single flagella on both ends of the clitinum (spiral); lophotrichs - with a tuft of flagella at one end of the clitini (fecal meadow-forming agent); peritrichs - flagella spread over the entire surface of the tissue (gut bacteria). The fluidity of bacteria occurs due to the growth of bacteria and the influx of excess factors.
Small 6. Variants of growth of spores and flagella in bacteria. I – superchids: 1 – central; 2 – subterminal; 3 – terminal; II - flagella: 1 - monotrichs; 2 – amphitrichs; 3 – lophotrichs; 4 - peritrichs
Drank or fimbriae- villi that grow on the surface of bacterial cells. The odors are short and thin due to the flagella and also have a helical structure. The drink is made from protein - pilina. Some (there are hundreds of them) serve to attach bacteria to the cells of animals and people, while others (alone) are associated with the transfer of genetic material from the cells to the cells.
Mycoplasma
Mycoplasmas are cells that do not rub the cell wall, but are lined with a trisphere lipoprotein cytoplasmic membrane. Mycoplasmas can be spherical, oval in shape, thread-like or star-shaped. According to Bergi's classification, mycoplasmas are seen in a large group. These microorganisms are given even more respect as people with a fiery nature. Dimensions vary: from several micrometers up to 125-150 nm. Friable mycoplasmas pass through bacterial filters and are called forms that are filtered.
Spirochetes
Spirochetes (div. Fig. 52) (from the Latin speira - vigin, chaite - hairy) are thin, sinuous, crumbly single-celled organisms that range in size from 5 to 500 microns at the edge and 0.3-0.75 microns at the top. The simplest method is to shorten the internal axial thread, which forms a bundle of fibrils. The nature of the spirochetes is different: progressive, obertal, gyral, quill-like. In other everyday life, the tissue is typical for bacteria. Some spirochetes are weakly barked with aniline barnacles. The spirochetes are divided into canopies behind a number of threads and the shape of the curls of the thread that ends. A mixture of saprophytic forms, which are widespread in nature and the human body, among spirochetes and pathogens - causes of syphilis and other illnesses.
Rickettsia
Viruses
Among viruses there is a group of phages (from the Latin phagos - devours), which cause lysis (ruining) of microorganisms. Saving power to viruses, power and storage, phages are divided by the structure of the virion (division 8). The stinks do not scream for the sickness of people and creatures.
Control food
1. Tell us about the classification of microorganisms.
2. Name the main powers of representatives of the kingdom of prokaryotes.
3. Revise and characterize the main forms of bacteria.
4. Name the main organs of the cell and their functions.
5. Give a brief description of the main groups of bacteria and viruses.