ANIMAL KINGDOM.
The main difference between an animal organism and a plant organism is that in animal cells there are no chloroplasts and no chlorophyll.
However, most animal and plant organisms have similar, i.e. identical life processes. For example, the breathing process. Almost all living organisms breathe oxygen while releasing carbon dioxide. The exception is some organisms, including a large group of anaerobic bacteria.
This releases the energy necessary for the existence of the organism. Actually, all living things are characterized by the process of metabolism. The body receives some things and throws others out.
the body in the process of respiration (carbon dioxide, water vapor, etc. are released), digestion (feces), sweat, urine. These are waste substances that are no longer needed by the body. In other words, metabolism occurs.
Metabolism is the main property of all life on Earth.
Oxygen, oxygen gives life to organisms -
In each cell, oxidation occurs in our
It’s like there’s a fire in a stove—the substances are boiling and bubbling.
And energy is released from us,
That’s why we walk, write and read, and hear everything.
After all, metabolism, of course, is the main property for us,
That’s why we live and breathe every moment and every hour.
MICROORGANISMS. Varieties, Ecological significance.
Microorganisms include very small organisms that can only be seen and examined under a microscope:
1.Eukaryotes are higher microorganisms (algae, fungi, protozoa). Their cells have a differentiated nucleus with a set of chromosomes, delimited from the cytoplasm by a nuclear membrane. The cytoplasm contains a developed endoplasmic reticulum, as well as mitochondria and ribosomes.
2. Prokaryotes - lower microorganisms (blue-green unicellular algae and bacteria). They do not have a differentiated nucleus; the DNA lies freely, immersed in the cytoplasm.
3. Viruses. Translated into Russian, the word virus means “poison”. The classification of viruses is based on the type of nucleic acid (DNA - viruses and RNA - viruses), the presence or absence of outer envelopes, as well as the number of capsomers in the capsid and the type of their folding (type of symmetry). Among them are a huge number of viruses that cause diseases in plants (tobacco mosaic disease), animals (mammal pox) and humans. The latter include adenoviruses (febrile diseases with symptoms of respiratory tract damage..), herpesviruses (herpes, chickenpox...), poxviruses (natural blackpox), myxoviruses (influenza, mumps, rubella).
BLUE-GREEN unicellular algae (a group of prokaryotic cyanobacteria)
They live primarily in water and are of great importance because they saturate the water with oxygen during the process of photosynthesis.
BACTERIA.
The average cell diameter is 1 micron, length varies from 0.1 to 10 microns. Bacteria have mastered a wide variety of habitats: they live in water, soil, dust, in the air, on the outer surfaces of plants and animals, including humans, as well as inside these organisms, often causing diseases. All bacteria are divided into 19 groups, which are of great importance for humans. There are bacteria that live with it and help it. Such symbionts include, for example, E. coli. She is the “mistress” of the large intestine (only the large intestine, no more). But among bacteria there are also those that cause diseases in both animals and humans (for example, anthrax...). Among the bacteria that cause diseases in humans are: spirochetes (syphilis), staphylococci, streptococci (pneumonia, sepsis), gonococci (gonorrhea), salmonella (typhoid fever, paratyphoid fever), shigella (dysentery), mycobacteria (tuberculosis), rickettsia ( typhus), chlamydia (trachoma) and others.
Based on morphology (external structure), bacteria are divided into three main groups:
rod-shaped (actually bacteria and bacilli);
spherical (staphylococci, streptococci, micrococci, diplococci, gonococci,
Tetracoccus, Sarcinus);
convoluted (vibrios, spirilla, spirochetes, leptospira).
Bacteria also play an important role in soil fertility.
They and other microorganisms, together with fungi, decompose and mineralize dead plant and animal remains, turning them into substances available for plant nutrition (humus). Without soil bacteria and fungi (true decomposers), annually falling leaves, pine needles, and animal remains would accumulate in huge quantities and prevent forest regeneration. This also applies to bodies of water.
This is the ecological significance of soil bacteria and other microorganisms. Their main function is to cleanse our common home.
Bacteria. These are single-celled prokaryotic organisms. Their size ranges from 0.5 to 10-13 microns. Bacteria were first observed under a microscope by Anthony van Leeuwenhoek in the 17th century.
A bacterial cell has a membrane (cell wall) similar to a plant cell. But in bacteria it is elastic, non-cellulose. Under the shell there is a cell membrane, which ensures the selective flow of substances into the cell. It protrudes into the cytoplasm, increasing the surface of membrane formations on which many metabolic reactions take place. A significant difference between a bacterial cell and the cells of other organisms is the absence of a formed nucleus. In the nuclear zone there is a circular DNA molecule, which is the carrier of genetic information and regulates all life processes of the cell. Of the other organelles in bacterial cells, only ribosomes are present, on which protein synthesis occurs. Prokaryotes lack all other organelles.
Rice. 59. Various forms of bacteria
The shape of bacteria is very diverse and forms the basis of their classification (Fig. 59). These are spherical - cocci, rod-shaped - bacilli, curved - vibrios, twisted - spirilla And spirochetes. Some bacteria have flagella that help them move. Bacteria reproduce by simply dividing a cell into two. Under favorable conditions, a bacterial cell divides every 20 minutes. If conditions are unfavorable, further proliferation of the bacterial colony is stopped or slowed down. Bacteria do not tolerate low and high temperatures well: when heated to 80 °C, many die, and some, under unfavorable conditions, form disputes- resting stages, covered with a dense shell. In this state they remain viable for quite a long time, sometimes several years. Some bacterial spores can withstand freezing and temperatures up to 129°C. Sporulation is characteristic of bacilli, for example, the causative agents of anthrax and tuberculosis.
Bacteria live everywhere - in soil, water, air, in the bodies of plants, animals and humans. Many bacteria according to the way they feed are heterotrophic organisms, i.e., they use ready-made organic substances. Some of them, being saprophytes, destroys the remains of dead plants and animals, participates in the decomposition of manure, and promotes soil mineralization. Bacterial processes of alcoholic and lactic acid fermentation are used by humans. There are species that can live in the human body without causing harm. For example, E. coli lives in the human intestines. Certain types of bacteria, settling on food products, cause their spoilage. Saprophytes include bacteria of decay and fermentation.
In addition to heterotrophs, there are also autotrophic bacteria that can oxidize inorganic substances and use the released energy for the synthesis of organic substances. For example, soil azotobacteria enrich it with nitrogen, increasing fertility. On the roots of leguminous plants - clover, lupine, peas - you can see nodules containing such bacteria. Autotrophs include sulfur bacteria and iron bacteria.
Another group of microorganisms belongs to prokaryotes - cyanobacteria. Cyanobacteria are autotrophs, have a photosynthetic system and the corresponding pigments. That's why they are green or blue-green in color. Cyanobacteria can be solitary, colonial, or filamentous (multicellular).
They are similar in appearance to algae. Cyanobacteria are common in water, soil, hot springs, and are part of lichens.
Mushrooms. This is a group of heterotrophic organisms that has characteristics similar to plants and animals.
Like plants, fungi have a cell wall, unlimited growth, they are immobile, reproduce by spores, and feed by absorbing nutrients dissolved in water.
Like animals, fungi are not able to synthesize organic substances from inorganic ones, do not have plastids and photosynthetic pigments, accumulate glycogen rather than starch as a reserve nutrient, and the cell membrane is built from chitin, not cellulose.
That is why mushrooms are classified into a separate kingdom. The kingdom of mushrooms unites about 100 thousand species that are widespread on Earth.
Rice. 60. The structure of mushrooms: 1 - mucor; 2 - yeast; 3 - penicillium
Mushroom body (Fig. 60) - thallus consists of thin threads - hyphae. A collection of hyphae is called mycelium or mycelium. Hyphae may have septa, forming individual cells. But in some cases there are no partitions (in mucor). Therefore, fungal cells can contain one or many nuclei.
The mycelium develops on the substrate, while the hyphae penetrate into the substrate and grow, branching repeatedly. Mushrooms reproduce vegetatively - by parts of mycelium and spores that mature in specialized cells - sporangia.
Mushrooms are divided into two classes: lower and higher mushrooms.
1. Lower mushrooms often have multinucleate mycelium or consist of a single cell. Representatives of lower fungi are mold fungi: mucor, penicillium, aspergillus. In penicillium, unlike mucor, the mycelium is multicellular, divided into partitions. Molds develop in the soil, on wet foods, in fruits and vegetables, causing them to spoil. One part of the fungal hyphae penetrates into the substrate, and the other part rises above the surface. Spores mature at the ends of vertical hyphae.
Yeast - These are lower unicellular fungi. Yeast does not form mycelium and reproduces by budding. They cause alcoholic fermentation, decomposing sugar in the process of their life activity. They are used in brewing, baking, and winemaking.
2. TO higher mushrooms relate cap mushrooms. They are characterized by multicellular mycelium, which develops in the soil and forms on the surface. fruiting bodies, consisting of tightly intertwined hyphae in which spores mature. The fruiting bodies consist of a stem and a cap. In some mushrooms, the lower layer of the cap is formed by radially arranged plates - this is lamellar mushrooms. These include russula, chanterelles, champignons, toadstool, etc. Other mushrooms have numerous tubes on the underside of the cap - these are tubular mushrooms. These include porcini mushroom, boletus, boletus, fly agaric, etc. Fungal spores ripen in tubes and on plates. Often the mycelium of the fungus forms mycorrhiza, growing by hyphae into plant roots. The plant supplies the fungus with organic nutrients, and the fungus provides mineral nutrition to the plant. Such mutually beneficial cohabitation is called symbiosis. Many cap mushrooms are edible, but some are poisonous.
1. Saprophytic mushrooms they feed on dead organisms, organic residues, food products, and ripened fruits, causing them to rot and decay. Saprophytes include mucor, penicillium, aspergillus, and most cap mushrooms.
Fungi, along with bacteria, play an important role in the cycle of substances in the biosphere. They decompose organic substances, mineralize them, and participate in the formation of a fertile soil layer - humus. The importance of mushrooms in human life is also great. In addition to being used as food, medicines are obtained from mushrooms - antibiotics (penicillin), vitamins, plant growth substances (gibberellin), enzymes.
Lichens. This is a unique group of organisms, representing a symbiosis of a fungus and unicellular algae or cyanobacteria. The fungus protects the algae from drying out and supplies it with water. And algae and cyanobacteria, through the process of photosynthesis, form organic substances that the fungus feeds on.
Lichen body - thallus (thallus) consists of fungal hyphae, among which are unicellular algae. The surface layer of lichen is formed by densely woven hyphae, and the lower ones are more sparse. Green algae are located among the sparse network of hyphae.
Such structural features of the lichen allow it not only to receive nutrition from the soil, but also to capture moisture and dust particles that settle on the thallus from the air. Therefore, lichens have a unique feature - they can exist in the most unfavorable conditions, settling on bare rocks and stones, tree bark, and house roofs. They are called “pioneers” of soil formation, since, by “inhabiting” rocks, they create conditions for the subsequent settlement of plants. The only necessary condition for the life of lichens is clean air. Therefore, they serve as indicators of the degree of air pollution.
Lichens reproduce vegetatively - by parts of the thallus and algae cells. They grow very slowly.
Based on their appearance, lichens are divided into three groups: crustose (scale), leafy and bushy (Fig. 61).
crustose lichens The thallus adheres tightly to the substrate, from which they cannot be separated. They are completely satisfied with a small amount of water that falls in the form of precipitation or is in the atmosphere in the form of vapor. They settle on tree trunks and stones.
Rice. 61. Lichens: A - structure (1 - green algae cells; 2 - fungal hyphae); B - variety: 2 - cortical, 3 - leafy, 4 - bushy
Xanthoria - Wall goldenrod is often found on aspen bark, board fences and roofs. Parmelia - a lichen with large lobes of gray-blue color, lives on the bark of pine trees and dead branches of spruce.
Foliaceous lichens can be found on the bark of trees, soil where there is no grass. They are attached to the substrate with the help of thin outgrowths of the thallus.
Peltiger - a gray-green lichen with black veins below, growing on the soil in damp places.
Fruticose lichens have a highly branched thallus. They grow mainly on soil, stumps, and tree trunks. They are attached to the substrate only by the base.
Iceland moss- a gray-yellow lichen with strongly curved narrow outgrowths of the thallus. Contains a lot of vitamin C, used for scurvy in the North. Reindeer moss, or reindeer moss, occupies large spaces in the tundra and serves as the main food for reindeer. These are graceful bushes consisting of thin, highly branched stems. When dry, it becomes brittle and crunches underfoot. It also grows in dry pine forests. Krasnogolovka- gray-green small, 3 cm, tubes, with a red edge or balls (heads) along the edge. Grows on old stumps. bearded man forms long hanging clumps, settling on trees in humid forests, most often on spruce trees.
Being autoheterotrophs, lichens create organic substances through the process of photosynthesis in places inaccessible to other organisms. At the same time, they mineralize organic matter, thereby participating in the cycle of substances in nature and playing an important role in soil formation.
| |
§ 50. System of classification of living organisms§ 52. Plants, their structure. Vegetative organs
The composition and distribution of the biosphere by mass is a rather interesting and significant issue in biology. Although an accurate census of all living organisms on Earth is literally impossible. It’s hard to imagine information like this: meet the bacteria Alice 43 by 10 to the 30th power, lives in a swamp near Ust-Kamenogorsk, sorry, while they were doing the census, Alice died, leaving 23 billion descendants. However, scientists were able to determine the biomass of the kingdoms of living organisms on the planet, as well as determine what influence humans had on its distribution. Although it’s too early to talk about super accuracy, the #infographics are very interesting.
results
Calculations were made in gigatons of carbon, because carbon compounds are the basis for all living things and make up about 17.5% of animals and plants, while this mass does not depend on the water content in them. 1 Gt C is equal to 10 to the 15th power of grams of carbon. According to scientists, the biomass of all kingdoms of life on the planet is 550 Gt of carbon. The lion's share of biomass is plants, about 450 Gt C, followed by bacteria 70 Gt C, fungi 12 Gt C, archaea 7 Gt C, protists 4 Gt C, animals 2 Gt C and viruses 0.2 Gt C.
Scientists also note that marine biomass, unlike terrestrial biomass, contains more consumers than producers. This refers to the food structure of the community, which is divided into consumers, producers and decomposers. Producers are organisms that create organic substances from inorganic ones, such as photosynthesis. Consumers consume the products of producers, but do not decompose them into inorganic substances, like decomposers. And decomposers are bacteria and fungi that decompose the remains of living beings into simple or inorganic substances. By the way, the error in counting bacteria in the results obtained is quite large.
It is also worth noting that, according to the data obtained, the underground biomass turned out to be less than aboveground, contrary to many statements of scientists. Which is understandable due to some gaps in our knowledge at the moment, especially in the underworld. But the mass of leaves is 6.5 times less than the entire mass of roots. Plant biomass includes ≈70% of tree stems and trunks, which are largely metabolically inert.
The following chart shows average data for the animal kingdom. Marine arthropods have the largest carbon mass with 1 Gt C, followed by fish with 0.7 Gt C, followed by mollusks, nematodes or roundworms and terrestrial arthropods with 0.2 Gt C each. Although terrestrial arthropods are significantly more represented in terms of species than marine ones their mass is 5 times less. Marine arthropods have individual species, such as arctic krill, whose mass is only 4 times less than all terrestrial arthropods. This type of krill can be put on a par with termites, whose mass is also 0.05 Gt C, slightly less than that of humans. Next come cnidarians - these are aquatic multicellular inhabitants that have stinging cells for hunting and protection; their mass is 0.1 Gt C. The same is the mass of all livestock on the planet, which consists mainly of cattle and pigs. But people occupy only 0.06 Gt C, which is almost two times less than livestock and 11.6 times less than fish. However, humans have 8.5 times more carbon mass than all wild mammals and 30 times more than wild birds. And domestic birds, among which chickens predominate, are 2.5 times more numerous than all wild birds.
The influence of humanity on the biosphere.
Distribution of biomass across environments and nutritional regimes for individual organisms.
General food chain, trophic levels.
Some animals eat plants. Others are the flesh of organisms that consume plant foods. And those, in turn, can be eaten by humans. But every living thing ever has a time, that’s how nature works.
Law of Nature Renewal
In fact, imagine if organisms existed forever? The world would have long ago experienced overpopulation, leading to a lack of stable nutrition, as well as global environmental pollution. Therefore, according to the laws existing in the biosphere, all living organisms are born, grow up, leave offspring, grow old and die. And the biosphere is thus updated every second!
Kingdoms of nature: plants, animals, fungi, bacteria
All of them are involved in this reasonable and balanced And when any organism ceases its vital activity, the hour of decomposition of matter into its components begins. And here bacteria and fungi come to the aid of nature itself. Why are fungi and bacteria called decomposers? This concept can be directly related to their activities.
Saprophytes
This is the scientific name for those organisms that obtain their nutrition from the remains of other animals and plants. These mainly include bacteria and fungi. They decompose dead flesh into “raw materials” - inorganic simple compounds, microelements, allowing nature to build new organisms from them or use them to feed existing ones. This is why fungi and bacteria are called decomposers. But with their destructive activity they bring more benefit than harm.
A world without saprophytes
Imagine what would happen if bacteria and fungi did not process dead cells? Life itself would probably have suffocated under the hourly increasing layer of dead remains. And saprophytes, by providing nutrition, seem to “recycle” dead tissue, acting as orderlies or janitors, helping to remove unnecessary things and recycle waste. That is why fungi and bacteria are called decomposers, utilizing the remains of dead organisms. The positive effect of this global biological process on the environment has now been scientifically proven.
Entertaining biology: bacteria, fungi, plants - saprophytes
The concept itself has Greek roots and comes from two words “rotten” and “plant”. What organisms can be attributed to this group?
- First of all, these are many bacteria. They decompose organic matter, cause rotting of food, and participate in mineralization and nitrogen fixation. And some bacteria even break down cellulose and form hydrocarbons. Some microorganisms are particularly demanding of the substrate: they use only certain types of organic matter (for example, dairy products) as food. Others are practically omnivorous and can feed on various organic compounds: alcohols, proteins, carbohydrates and acids.
- Many large mushrooms can also be included in this group. After all, straw and humus, fallen leaves, manure, feathers, fallen antlers and much more serve them as a substrate with nutrients. As a rule, it lives on the remains of foliage and trees, and conifers are chosen. The white dung beetle develops in nitrogen-rich places. And they spoil human food, making it unusable. Many fungi enter into symbiosis with higher plants, processing their waste into microelements that plants can feed from the soil. This process is mutually beneficial and is sometimes reflected in the very names of the mushrooms: boletus, boletus. A group of predatory fungi that feed on small insects can also be conditionally classified as saprophytes. Because when there is no live prey, they can feed on dead organic matter.
- There are saprophytes among fauna representatives. These include: sundew, mistletoe, dodder, for example.
Now you know why fungi and bacteria are called decomposers (rather, they mean their positive role in nature). All saprophytes and saprophages are “responsible” for the circulation of substances in the biosphere and the disposal of dead organisms, without which, probably, the planet would cease to exist.
The main characteristics of living things: SELF-RENEWALING, SELF-REPRODUCTION and SELF-REGULATION.
They define and basic properties of living things:
1) MATERIALITY;
2) STRUCTURED - living organisms have a complex structure;
3) METABOLISM - living organisms receive energy from the environment and use it to maintain their high orderliness;
4) MOVEMENT;
5) HEREDITARY and VARIABILITY - living organisms not only change, but also become more complex; and are also able to transmit to their descendants the information embedded in them, necessary for life, development and reproduction;
6) REPRODUCTION - all living things reproduce;
7) IRRITABILITY - the ability to respond to external irritations;
8) ONTO- and PHYLOGENESIS;
9) DISCRETE;
10) INTEGRITY.
Generalizing and somewhat simplifying what has been said about the specifics of living things, we can say that all living organisms eat, breathe, grow, reproduce and spread in nature, while inanimate bodies do not feed, do not breathe, do not grow and do not reproduce.
Kingdom of Viruses.
Their peculiarities : small size; lack of cellular structure; simple chemical composition; the impossibility of existing outside the host's body.
Form viruses: rod-shaped, filiform, spherical, cuboid, club-shaped.
Mature virus particles - virions- consist of two main components: DNA or RNA and protein.
Viruses are the causative agents of many plant and animal diseases. In past centuries, viral infections were epidemic in nature, covering vast territories.
For example, in Europe, 10-12 million people fell ill with smallpox and 1.5 million people died. Of particular note is measles. Today, more than 2 million children die from measles every year.
Viral diseases cause enormous damage to agriculture. The foot and mouth disease virus is very dangerous for animals. Appearance , the most probable hypothesis seems to be one that interprets viruses as a result of the degradation of cellular organisms. There is another opinion that viruses can be considered as groups of genes that have escaped the control of the cell genome.
Kingdom Bacteria .
Age The most ancient bacteria are at least 3-3.5 billion years old. Many bacteria, according to scientists, appeared relatively recently. They emerge from the ice of the Arctic and Antarctica, penetrate oil wells, live in the water of hot springs, the temperature of which reaches 92°C, abundantly inhabit all types of soils and water bodies, and rise with air currents to a height of 85 km.
Bacteria in Greek means rod. Bacteria were discovered by the Dutchman A. Leeuwenhoek in 1675, but only Louis Pasteur for the first time showed the role of bacteria in the process of fermentation and other transformations of substances in nature. There are 5,000 species of bacteria.
FEATURES OF THEIR STRUCTURE:
§ small dimensions (0.0001 mm);
§ a typical prokaryotic cell, there is no separate nucleus, mitochondria, plastids, Golgi complex, nucleolus, chromosomes, etc.;
§ special structure and composition of membrane structures and cell walls;
§ The shape of the cells can be spherical, rod-shaped and convoluted.
Among bacteria, according to the source of energy used, they are distinguished PHOTOTROPHES and CHEMOTROPHS.
Photosynthetic bacteria use light energy to synthesize organic substances. Chemosynthetic bacteria use energy released during the oxidation of any inorganic substances in the environment to synthesize organic substances.
AUTOTROPHIC - capable of synthesizing organic substances of their body from inorganic compounds.
HETEROTROPHIC - unable to synthesize organic substances from inorganic ones, therefore they require the supply of ready-made organic substances from the outside in the form of food.
SAPROPHYTES are bacteria that settle on dead, remains of plants and animals.
Kingdom of Mushrooms.
The kingdom of Mushrooms has 100,000 species, diverse in structure and lifestyle. Mushrooms is a separate group of cellular nuclear heterotrophic organisms that are similar to both animals and plants.
Signs of similarity between mushrooms and animals: the nature of metabolism associated with the formation of urea; heterotrophic type of nutrition; chitin content in the cell wall; formation of a reserve product - glycogen.
Signs of similarity between mushrooms and plants: nutrition by absorption; unlimited growth; the presence of a cell wall in the cells; reproduction with spores.
STRUCTURE OF MUSHROOMS
The body of the mushroom consists of special intertwining threads - hyphae (mycelium). The cap mushroom consists of a mycelium and a fruiting body. And the fruit part is made from a cap and a stump.
A characteristic feature of fungi is their heterotrophy : some fungi settle on the dead remains of plants and animals; some feed on living things; some enter into symbiosis with plants.
Reproduce fungi asexually and sexually. Asexual reproduction is carried out vegetatively and by spores. The forms of sexual reproduction in fungi are varied and are divided into three groups: gametogamy, gametangiogamy, and somatogamy.
ROLE OF MUSHROOMS. Fungi are the main group of decomposers in ecosystems. They participate in soil formation, act as orderlies, and serve as food and medicine for animals.
