22. Characteristics of agroecosystems. Give examples. Agrosystem - A biotic community created by man and regularly maintained by him to obtain the products of one or several selected species (varieties, breeds) of plants or animals. Main goal creation of an agricultural system - rational use those biological resources that are involved in human activity - sources food products, technological raw materials, medicines. This also includes species specially cultivated by humans that are objects of agricultural production: fur farming, special cultivation of forest crops, as well as species used for industrial technologies.
23.Biosphere. Teachings of V.I. Vernandsky.
The biosphere is the shell of the Earth populated by living organisms.
The largest Russian scientist of the twentieth century. Vladimir Ivanovich Vernadsky (1863-1945) created the doctrine of the biosphere. In this teaching, he showed what a huge role living organisms play in geochemical processes on our planet.
At the end of his life, Vernadsky comes to the conclusion that the biosphere is closely related to human activity; The preservation of the equilibrium of the composition of the biosphere depends on this activity. He introduces a new concept - the noosphere, which means “thinking shell”, that is, the sphere of the mind. Vernadsky wrote: “Humanity, taken as a whole, becomes a powerful geological force. Before him, before his thought and work, there arises the question of restructuring the biosphere in the interests of free-thinking humanity as a single whole. This new state of the biosphere, to which we are approaching without noticing it, is the noosphere.”
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PLANT NUTRITION- assimilation of inorganic connections from environment and their autotrophic transformation into organic. in va, used for the formation and renewal of structural parts of soil and for energy. providing functions. Until the beginning 19th century there was a humus theory... Agricultural encyclopedic dictionary
plant nutrition- plant nutrition, absorption Not organic compounds from the environment and their autotrophic transformation into organic substances used for the formation and renewal of structural parts of plants and for energy supply of functions. Before we start... Agriculture. Large encyclopedic dictionary
The order Euglenoidea is of significant interest, since within this group all types of nutrition are found, from typically plant (autotrophic) to typically animal (animal). Numerous species of the genus Euglena... ... Biological encyclopedia
The most important components of the soil are microscopic plants and animals that live in it in huge numbers and take part in a number of basic transformations of substances that occur in the soil. It can be said without exaggeration that the big... Biological encyclopedia
HETEROTROPHS, organisms that use ready-made organic matter (usually plant or animal tissue) for their nutrition through a process known as heterotrophic nutrition. All animals and fungi are heterotrophs. As a result of digestive... Scientific and technical encyclopedic dictionary
- (Plantae, or Vegetabilia), the kingdom of living organisms; autotrophic organisms, which are characterized by the ability to photosynthesize and the presence of dense cell walls, usually consisting of cellulose; The reserve substance is usually starch. Biological encyclopedic dictionary
One of the kingdoms organic world. The most important difference between plants and other living organisms is the ability for autotrophic nutrition, that is, the synthesis of all necessary organic matter from inorganic. At the same time, green plants use energy... ... Encyclopedic Dictionary
The world of living beings has about 2 million species. All this diversity of organisms is studied by systematics, whose main task is the construction of systemic systems. m. After the triumph of evolutionary teaching (See. Evolutionary doctrine) V… … Great Soviet Encyclopedia
SYSTEMATICS AND ITS TASKS A special branch of biology called systematics deals with the classification of organisms and the elucidation of their evolutionary relationships. Some biologists call systematics the science of diversity (diversity... ... Biological encyclopedia
Polyphyletic group of protists Amoeba proteus ... Wikipedia
Autotrophic and heterotrophic nutrition of plant organisms
According to the nature of the food used in the process of life, all living organisms are divided into autotrophic and heterotrophic. Inorganic compounds - CO 2, H 2 O, etc. - serve as the main food for autotrophic organisms (most plants), which synthesize organic substances from them by photosynthesis or chemosynthesis: proteins, fats, carbohydrates, which constitute the food of heterotrophic organisms (a number of plants, all Mushrooms, animals and humans). In addition to proteins, fats and carbohydrates, heterotrophic organisms need vitamins, nucleic acids and microelements.
Heterotrophs are organisms that are not able to synthesize organic substances from inorganic ones. To synthesize the organic substances necessary for their life, they require organic substances produced by other organisms. During the digestion process, digestive enzymes break down polymers of organic substances into monomers. In communities, heterotrophs are consumers of various orders and decomposers.
Some organisms (for example, carnivorous plants) combine the characteristics of both autotrophs and heterotrophs. Such organisms are called mixotrophs.
In symbiotic feeding, one organism feeds on the waste of another without harming it. For example, nitrifying bacteria living on legumes supply them with nitrogen. Mammalian intestines contain bacteria that help break down nutrients, such as E. coli. Due to the harmlessness of this bacterium to humans, it is widely used in the creation of BSS.
In saprophytic feeding, organisms secrete enzymes onto dead or decaying organic material. These include fungi, a number of bacteria and insects. Some saprophytes secrete protease enzymes that can decompose proteins and dissolve the membranes of other cells, including pathogenic ones. Therefore, proteases are widely used as biotechnology objects in detergents, as well as in WSS for the detection of various protein-substrates specific to them using enzymatic reactions
Describe the functions and structure of root hairs
Different parts of the root perform different functions and are characterized by certain morphological features. The entry of soil solution into the root occurs primarily through the suction zone, so the larger the surface of this area of the root, the better it performs its main suction function. It is in connection with this function that some of the skin cells are elongated into root hairs 0.1-8 mm long. Root hairs appear in the form of small papillae - outgrowths of epiblema cells. Hair growth occurs at its apex. The root hair sheath stretches quickly. After a certain time, the root hair dies off. Its lifespan does not exceed 10-20 days.
Almost the entire root hair cell is occupied by a vacuole, surrounded by a thin layer of cytoplasm. The nucleus is located in the cytoplasm near the tip of the hair. Root hairs are able to embrace soil particles, as if fused with them, which facilitates the absorption of water and minerals from the soil. Absorption is also facilitated by the secretion of various acids by root hairs (carbonic, malic, citric, oxalic), which dissolve soil particles.
Root hairs form very quickly (in young apple tree seedlings within 30-40 hours). For 1 sq. mm of root, under favorable conditions, up to 300-400 root hairs are formed, which create a huge absorbing surface. One individual four-month-old rye plant has approximately 14 billion root hairs with an absorption area of about 400 m2 and a total length of more than 10 thousand km; the surface of the entire root system, including root hairs, is approximately 640 m2, i.e. 130 times more than escape. Root hairs do not function for long - usually 10-20 days. The average lifespan of a grape hair is from 10 to 40 days. Dead root hairs in the lower part of the root are replaced by new ones. Thus, the most active, suction zone of the roots constantly moves deeper and laterally following the growing tips of the root system branches. At the same time, the total suction surface of the roots increases all the time.
Each hair is an elongated cell. In connection with root growth, movement and renewal of the absorbent zone, a constant change of hairs occurs, ensuring continuous active work root system (Androsov, 2006).
Autotrophs do not eat anyone; they make organic substances themselves from inorganic ones.
- Auto phototrophs- energy is obtained from light (photosynthesis). Phototrophs include plants and photosynthetic bacteria.
- Auto chemotrophs- energy is obtained from oxidation inorganic substances(chemosynthesis). For example,
- sulfur bacteria oxidize hydrogen sulfide to sulfur,
- iron bacteria oxidize divalent iron to trivalent,
- Nitrifying bacteria oxidize ammonia to nitric acid.
Similarities and differences between photosynthesis and chemosynthesis
- Similarities: all this is a plastic exchange, organic substances are made from inorganic substances (from carbon dioxide and water - glucose).
- Difference: energy for synthesis in photosynthesis is taken from light, and in chemosynthesis - from redox reactions.
Heterotrophs
Heterotrophs obtain organic substances in finished form with food. Heterotrophs include animals, fungi and most bacteria.
Tests and assignments
Choose one, the most correct option. What is mycorrhiza?
1) mushroom root
2) the root system of the plant
3) mycelium that has spread in the soil
4) fungal threads forming the fruiting body
Answer
Choose three options. Autotrophs include
1) spore plants
2) molds
3) unicellular algae
4) chemotrophic bacteria
5) viruses
6) most protozoa
Answer
1. Establish a correspondence between a group of organisms and the process of transformation of substances that is characteristic of it: 1) photosynthesis, 2) chemosynthesis
A) ferns
B) iron bacteria
B) brown algae
D) cyanobacteria
D) green algae
E) nitrifying bacteria
Answer
2. Establish a correspondence between the examples and methods of nutrition of living organisms: 1) phototrophic, 2) chemotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) spirogyra
B) nitrifying bacterium
B) chlorella
D) sulfur bacteria
D) iron bacteria
E) chlorococcus
Answer
Establish a correspondence between the characteristics of organisms and their method of nutrition: 1) phototrophic, 2) chemotrophic. Write numbers 1 and 2 in the correct order.
A) light energy is used
B) oxidation of inorganic substances occurs
B) reactions take place in thylakoids
D) accompanied by the release of oxygen
D) is characteristic of hydrogen and nitrifying bacteria
E) requires the presence of chlorophyll
Answer
Answer
Answer
1. Establish a correspondence between the example and the method of nutrition: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the correct order.
A) cyanobacteria
B) kelp
B) bovine tapeworm
D) dandelion
D) fox
Answer
2. Establish a correspondence between the organism and the type of nutrition: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) Siberian pine
B) Escherichia coli
B) human amoeba
D) penicillium
D) horsetail
E) chlorella
Answer
3. Establish a correspondence between a single-celled organism and the type of nutrition that is characteristic of it: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) Vibrio cholerae
B) iron bacteria
B) malarial plasmodium
D) chlamydomonas
D) cyanobacterium
E) dysenteric amoeba
Answer
4. Establish a correspondence between the examples and methods of nutrition: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) spirogyra
B) bovine tapeworm
B) horsetail
D) sulfur bacteria
D) green grasshopper
Answer
5. Establish a correspondence between the examples and methods of nutrition: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) chlorella
B) frog
B) champignon
D) fern
D) kelp
Answer
COLLECTING 6:
A) mukor
B) nitrifying bacteria
B) tinder fungus
Choose one, the most correct option. By way of feeding, the vast majority of bacteria
1) autotrophs
2) saprotrophs
3) chemotrophs
4) symbionts
Answer
1. Establish a correspondence between the organism and its method of nutrition: 1) phototrophic, 2) heterotrophic, 3) chemotrophic. Write the numbers 1, 2 and 3 in the correct order.
A) spirogyra
B) penicillium
B) sulfur bacteria
D) cyanobacterium
D) earthworm
Answer
2. Establish a correspondence between organisms and their types of nutrition: 1) phototrophic, 2) heterotrophic. Write numbers 1 and 2 in the order corresponding to the letters.
A) lamblia
B) ergot mushroom
B) chlamydomonas
D) cyanobacterium
D) sphagnum
Answer
Establish a correspondence between a metabolic feature and the group of organisms for which it is characteristic: 1) autotrophs, 2) heterotrophs
A) release of oxygen into the atmosphere
B) the use of energy contained in food for the synthesis of ATP
C) the use of ready-made organic substances
D) synthesis of organic substances from inorganic ones
D) use of carbon dioxide for nutrition
Answer
Choose one, the most correct option. What organisms convert the energy of oxidation of inorganic substances into high-energy bonds of ATP?
1) phototrophs
2) chemotrophs
3) heterotrophs
4) saprotrophs
Answer
Choose one, the most correct option. The similarity between chemosynthesis and photosynthesis is that in both processes
1) solar energy is used to form organic substances
2) the energy released during the oxidation of inorganic substances is used for the formation of organic substances
3) carbon dioxide is used as a carbon source
4) released into the atmosphere final product- oxygen
Answer
Answer
Choose one, the most correct option. Which organism is classified as heterotroph based on its feeding method?
1) chlamydomonas
2) kelp
3) penicillium
4) chlorella
Answer
Choose one, the most correct option. Mycorrhiza fungus is
1) mycelium on which fruiting bodies develop
2) many elongated cells
3) complex interweaving of hyphae
4) cohabitation of fungus and plant roots
Answer
Answer
Establish a correspondence between the characteristics and the feeding method of organisms: 1) autotrophic, 2) heterotrophic. Write numbers 1 and 2 in the correct order.
A) the source of carbon is carbon dioxide
B) accompanied by photolysis of water
C) the energy of oxidation of organic substances is used
D) the energy of oxidation of inorganic substances is used
D) food intake by phagocytosis
Answer
Establish a correspondence between the nutritional characteristics of the organism and the group of organisms: 1) autotrophs, 2) heterotrophs. Write numbers 1 and 2 in the order corresponding to the letters.
A) capture food by phagocytosis
B) use the energy released during the oxidation of inorganic substances
C) obtain food by filtering water
D) synthesize organic substances from inorganic ones
D) use the energy of sunlight
E) use the energy contained in food
Answer
Chemosynthetic bacteria are able to obtain energy from the compounds of all elements except two. Identify two elements that “drop out” from the general list and write down the numbers under which they are indicated.
1) Nitrogen
2) Chlorine
3) Iron
4) Magnesium
5) Sulfur
Answer
1. Identify two organisms that “drop out” from the list of autotrophic organisms and write down the numbers under which they are indicated.
1) Amoeba vulgaris
2) Venus flytrap
3) Pinularia green
4) Ciliate slipper
5) Spirogyra
Answer
2. All the organisms given below, except two, are classified as autotrophs based on the type of nutrition. Identify two organisms that “drop out” from the general list and write down the numbers under which they are listed.
1) chlamydomonas
2) horsetail
3) boletus
4) cuckoo flax
5) yeast
Answer
3. All the organisms given below, except two, are classified as autotrophs based on the type of nutrition. Identify two organisms that “drop out” from the general list and write down the numbers under which they are listed.
1) sulfur bacteria
2) spirogyra
3) fly agaric
4) sphagnum
5) bacteriophage
Answer
4. All the organisms given below, except two, are classified as autotrophs based on the type of nutrition. Identify two organisms that “drop out” from the general list and write down the numbers under which they are listed.
1) cyanobacterium
2) amoeba
3) kelp
4) sphagnum
5) penicillium
Answer
Choose one, the most correct option. Decay bacteria are based on the way they feed on organisms
1) chemotrophic
2) autotrophic
3) heterotrophic
4) symbiotic
Answer
Choose three correct answers out of six and write down the numbers under which they are indicated. Mycorrhizae form
1) birch and boletus
2) birch and birch chaga
3) aspen and boletus
4) pine and boletus
5) corn and smut
6) rye and ergot
Answer
1. Choose three correct answers out of six and write down the numbers under which they are indicated. Examples of symbiotic relationships are:
1) tinder fungus and birch
2) sundew and insects
3) nodule bacteria and legumes
4) cellulose-degrading bacteria and herbivores
5) cannibalism in predatory fish
6) sea anemone and hermit crab
Answer
2. Choose three correct answers out of six and write down the numbers under which they are indicated. In a mixed forest ecosystem, a symbiotic relationship is established between
1) birch and spruce trees
2) birch trees and tinder fungi
3) aphids and ants
4) hedgehogs and insectivorous birds
5) birches and boletus
6) bird cherry and its pollinating flies
Answer
Establish the sequence of stages of the nitrogen cycle in nature, starting with free atmospheric nitrogen. Write down the corresponding sequence of numbers.
1) absorption of atmospheric nitrogen by bacteria
2) conversion of free nitrogen into bound forms
3) consumption of fixed nitrogen by animals
4) denitrification of fixed nitrogen by bacteria
5) absorption of nitrogen compounds by plants
Answer
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Heterotrophic method of plant nutrition
General characteristics heterotrophic plants
Thus, heterotrophic nutrition of cells and tissues becomes common, as does photosynthesis.
The heterotrophic method of nutrition is the assimilation of both low molecular weight organic compounds and high molecular weight ones (proteins, fats, carbohydrates), but they must undergo processing - digestion. In plants, there are 3 types of digestion: intracellular - in the cytoplasm, vacuoles, plastids, protein bodies, spherosomes; membrane, carried out by enzymes cell membranes; extracellular - enzymes formed in special cells are released into the external environment and act outside the cells.
Saprophytes
The mechanisms of saprophytic nutrition of plants and fungi are similar. In the plasmalemma of fungal hyphae there is a H + -pump (hydrogen pump), with the help of which acid hydrolases are released into the environment. This leads to the hydrolysis of complex organic compounds, which are then absorbed by the fungus. The absorption mechanism is also associated with the operation of the H + pump in the plasmalemma. When the outer membrane zone is acidified, the dissociation of organic acids decreases and they penetrate into cells in the form of neutral molecules. This method is common in algae (diatoms that live at depths where light does not penetrate and feed on organic matter from the environment). When there is a large amount of soluble organic matter in water bodies, chlorococcal, euglena and other algae switch to heterotrophic nutrition.
U angiosperms The saprophytic method of nutrition is rare. These plants have little or no chlorophyll and are not capable of photosynthesis. To build their bodies, they use the rotting remains of plants and animals. Gidiophytum formicarum - a subshrub, the stem of which forms a large tuber, penetrated by numerous passages in which ants settle. The plant uses the waste products of ants as food. The tagged fly larvae were digested by the plant after a month.
Mycorrhiza is used by most plants mainly to increase the absorption of water and mineral salts.
Rafflesia feeds on the juices of the roots of tropical vines. It penetrates into the host's body with the help of haustoria, which secrete enzymes that destroy cell walls. Rafflesia spends its entire life in the body of the owner - underground. Only its flowers (diameter 1.5 m, red with the smell of rotting meat) appear on the surface of the soil.
Carnivorous plants
Currently, over 400 species of angiosperms and insectivorous plants are known. They catch small insects and other organisms, digest them and use them as an additional source of food. Most of them are found on nitrogen-poor swampy soils; there are epiphytic and aquatic forms. The leaves of insectivorous plants are transformed into special traps that also perform the function of photosynthesis. According to the method of catching it, plants are divided into two groups. 1) Passive fishing, prey a) sticks to the leaves, the glands of which secrete sticky mucus containing acidic polysaccharides (Biblis, rosewort), or b) falls into special traps in the form of jugs, urns, tubes, painted in bright colors and releasing a sweet aromatic secret (sarracenia, darlingtonia).
2) Active capture of insects a) gluing prey with sticky mucus and enveloping it with a leaf or hairs (butterfly, sundew), b) catching according to the trap principle - with the slamming of trapping leaves over the prey (aldrovanda, Venus flytrap), c) trapping bubbles into which insects are drawn in with water due to the vacuum maintained in them (pemphigus).
Common to all trapping devices is the attraction of insects with the help of polysaccharide mucus or aromatic secretion (nectar), secreted either by the trapping devices themselves, or by glands near the trap. Rapid movements of the hunting organs are carried out by changes in turgor in them in response to irritation of sensitive hairs caused by the movements of the insect.
Digestion.An insect caught in a trap is digested under the influence of the secretion of numerous glands. Some insectivores paralyze their prey with alkaloids contained in the secreted mucus (sundewdews secrete the alkaloid conitine, which paralyzes the insect). Sticky mucus contains many acidic polysaccharides consisting of xylose, mannose, galactose and glucuronic acid, organic acids and a number of hydrolases that are active in an acidic environment. Acidic mucous secretions, nitrogen- and phosphorus-containing decomposition products stimulate the work of glands that secrete acids (formic, benzoic), as well as proteases and a number of other hydrolases. The proteolytic activity of the flycatcher secretion has been studied in some detail. Secretory cells have a well-developed ER and Golgi apparatus, which produce large number secret.
Absorption of decomposition products is carried out by the same glands connected to the conductive system (after 5 minutes). The dominant role in the transport of digestive products belongs to simplast. Thus, the process of digestion in insectivorous plants is carried out fundamentally in the same way as in the stomach of animals. In both cases, acids are secreted ( HCI - in the stomach, formic acid- in insectivorous plants). The acidic reaction of digestive juice in itself promotes the digestion of animal food. The fundamental similarity of the process of acidic extracellular digestion in animals and plants was first pointed out by Darwin in his book “Insectivorous Plants.”
It is currently known that acidification of the environment in the stomach of animals occurs as a result of the functioning of the H + pump in the plasmalemma of the cells of the gastric mucosa.
Many insectivorous plants live on soils poor in mineral elements. Their root system is poorly developed, there is no mycorrhiza, so the absorption of mineral elements from caught prey is important for them great value. From the body of the prey, insectivorous plants obtain nitrogen, phosphorus, potassium, and sulfur. Carbon contained in amino acids and other breakdown products is also involved in the metabolism of insectivorous plants. (Darwin also showed that if sundew plants are fed with pieces of meat, then after three months they are significantly superior to control plants in a number of indicators, especially reproductive ones. It has been established that bladderwort plants bloom only after receiving animal food).
