Human food chain examples. Lesson topic "food chain"

Types of power circuits

What does the length of the power circuit mean?

What is the basis of the food chain?

Power circuits, video film

Pastoral food chain

Detrital food chain

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Human food chain examples. Lesson topic "food chain"

Introduction

1. Food chains and trophic levels

2. Food webs

3. Freshwater food connections

4. Forest food connections

5. Energy losses in power circuits

6. Ecological pyramids

6.1 Pyramids of numbers

6.2 Biomass pyramids

Conclusion

Bibliography

Introduction

Organisms in nature are connected by a commonality of energy and nutrients. The entire ecosystem can be likened to a single mechanism that consumes energy and nutrients to do work. Nutrients initially originate from the abiotic component of the system, to which they are ultimately returned either as waste products or after the death and destruction of organisms.

Within an ecosystem, energy-containing organic substances are created by autotrophic organisms and serve as food (a source of matter and energy) for heterotrophs. Typical example: An animal eats plants. This animal, in turn, can be eaten by another animal, and in this way energy can be transferred through a number of organisms - each subsequent one feeds on the previous one, supplying it with raw materials and energy. This sequence is called a food chain, and each link is called a trophic level.

The purpose of the essay is to characterize food connections in nature.

1. Food chains and trophic levels

Biogeocenoses are very complex. They always contain many parallel and complexly intertwined food chains, and the total number of species is often measured in hundreds and even thousands. Almost always different types They feed on several different objects and themselves serve as food for several members of the ecosystem. The result is a complex network food connections.

Each link in the food chain is called a trophic level. The first trophic level is occupied by autotrophs, or the so-called primary producers. Organisms of the second trophic level are called primary consumers, the third - secondary consumers, etc. There are usually four or five trophic levels and rarely more than six.

The primary producers are autotrophic organisms, mainly green plants. Some prokaryotes, namely blue-green algae and a few species of bacteria, also photosynthesize, but their contribution is relatively small. Photosynthetics convert solar energy(light energy) into chemical energy contained in the organic molecules from which tissues are built. Chemosynthetic bacteria, which extract energy from inorganic compounds, also make a small contribution to the production of organic matter.

In aquatic ecosystems, the main producers are algae - often small single-celled organisms that make up phytoplankton surface layers oceans and lakes. On land most of primary production supply more highly organized forms related to gymnosperms and angiosperms. They form forests and meadows.

Primary consumers feed on primary producers, i.e. they are herbivores. On land, typical herbivores include many insects, reptiles, birds and mammals. The most important groups of herbivorous mammals are rodents and ungulates. The latter include grazing animals such as horses, sheep, large cattle, adapted for running on the tips of the fingers.

In aquatic ecosystems (freshwater and marine), herbivorous forms are usually represented by mollusks and small crustaceans. Most of these organisms—cladocera and copepods, crab larvae, barnacles, and bivalves (such as mussels and oysters)—feed by filtering out the smallest primary producers of water. Together with protozoa, many of them form the bulk of the zooplankton that feed on phytoplankton. Life in oceans and lakes depends almost entirely on plankton, since almost all food chains begin with it.

Plant material(for example, nectar) → fly → spider →

→ shrew → owl

Juice rose bush→ aphid → ladybug → spider → insectivorous bird→ bird of prey

There are two main types of food chains - grazing and detrital. Above were examples of pasture chains in which the first trophic level is occupied by green plants, the second by pasture animals and the third by predators. Bodies dead plants and animals still contain energy and " construction material”, as well as intravital excretions, such as urine and feces. These organic materials are decomposed by microorganisms, namely fungi and bacteria, living as saprophytes on organic residues. Such organisms are called decomposers. They release digestive enzymes onto dead bodies or waste products and absorb the products of their digestion. The rate of decomposition may vary. Organic matter from urine, feces and animal carcasses is consumed within weeks, while fallen trees and branches can take many years to decompose. A very significant role in the decomposition of wood (and other plant debris) is played by fungi, which secrete the enzyme cellulose, which softens the wood, and this allows small animals to penetrate and absorb the softened material.

Pieces of partially decomposed material are called detritus, and many small animals (detritivores) feed on them, speeding up the decomposition process. Since both true decomposers (fungi and bacteria) and detritivores (animals) are involved in this process, both are sometimes called decomposers, although in reality this term refers only to saprophytic organisms.

Larger organisms can, in turn, feed on detritivores, and then a different type of food chain is created - a chain, a chain starting with detritus:

Detritus → detritivore → predator

Detritivores of forest and coastal communities include earthworm, woodlice, carrion fly larva (forest), polychaete, scarlet fly, holothurian (coastal zone).

Here are two typical detrital food chains in our forests:

Leaf litter → Earthworm → Blackbird → Sparrowhawk

Dead animal → Carrion fly larvae → Grass frog → Common grass snake

Some typical detritivores are earthworms, woodlice, bipeds and smaller ones (<0,5 мм) животные, такие, как клещи, ногохвостки, нематоды и черви-энхитреиды.

2. Food webs

In food chain diagrams, each organism is represented as feeding on other organisms of one type. However, actual food relationships in an ecosystem are much more complex, since an animal may feed on different types of organisms from the same food chain or even from different food chains. This is especially true for predators of the upper trophic levels. Some animals eat both other animals and plants; they are called omnivores (this is the case, in particular, with humans). In reality, food chains are intertwined in such a way that a food (trophic) web is formed. A food web diagram can only show a few of the many possible connections, and it usually includes only one or two predators from each of the upper trophic levels. Such diagrams illustrate nutritional relationships between organisms in an ecosystem and provide the basis for quantitative studies of ecological pyramids and ecosystem productivity.

3. Freshwater food connections

The food chains of a fresh water body consist of several successive links. For example, protozoa, which are eaten by small crustaceans, feed on plant debris and the bacteria that develop on them. The crustaceans, in turn, serve as food for fish, and the latter can be eaten by predatory fish. Almost all species do not feed on one type of food, but use different food objects. Food chains are intricately intertwined. An important general conclusion follows from this: if any member of the biogeocenosis falls out, then the system is not disrupted, since other food sources are used. The greater the species diversity, the more stable the system.

The primary source of energy in aquatic biogeocenosis, as in most ecological systems, is sunlight, thanks to which plants synthesize organic matter. Obviously, the biomass of all animals existing in a reservoir completely depends on the biological productivity of plants.

All living beings on our planet are connected to each other by one of the strongest connections - food. That is, someone is food for someone else, or, in scientific terms, a food supply. Herbivores eat plants, the herbivores themselves are eaten by predators, which in turn can also be eaten by other, larger and stronger predators. In biology, these peculiar food connections are usually called food chains. Understanding how the food chain ecosystem works gives biologists an understanding of the various nuances of living organisms, helps explain the behavior of some animals, and understands where the legs come from for certain habits of our four-legged friends.

In general, there are two main types of food chains: the grazing chain (also known as the grazing food chain) and the detrital food chain, which is also called the decomposition chain.

The pasture food chain is generally simple and understandable; its essence is briefly described at the beginning of the article: plants serve as food for herbivores and in scientific terminology are called producers. Herbivores that eat plants are called consumers (from Latin this word is translated as “consumers”) of the first order. Small predators are consumers of the second order, and larger ones are of the third order. In nature, there are also longer food chains, numbering five or more links, these are found mainly in the oceans, where larger (and voracious) fish eat smaller ones, which in turn eat even smaller ones, and so on down to algae. The links in the food chain are closed by a special happy link, which no longer serves as food for anyone. Usually this is a person, of course, provided that he is careful and does not try to swim with sharks or walk with lions)). But seriously, such a closing link of nutrition in biology is called a decomposer.

But here everything happens a little the other way around, namely, the energy flow of the food chain goes in the opposite direction: large animals, whether predators or herbivores, die and decompose, their remains feed on smaller animals, various scavengers (for example, hyenas), which in their turn also die and decompose, and their mortal remains similarly serve as food, either for even smaller lovers of carrion (for example, some species of ants), or for various special microorganisms. Microorganisms, processing the remains, release a special substance called detritus, hence the name of this food chain.

A more visual diagram of the power circuit is shown in the picture.

Studying the length of the food chain gives scientists answers to many questions, for example, how favorable the environment is for animals. The more favorable the habitat, the longer the natural food chain will be due to the abundance of different animals serving each other as food. But the longest food chain is for fish and other inhabitants of the ocean depths.

The basis of any food chain is food connections and energy, which is transferred with the consumption of one representative of the fauna (or flora) to another. Thanks to the energy received, consumers can continue their life activities, but in turn they also become dependent on their food (feed base). For example, when the famous migration of lemmings occurs, serving as food for various arctic predators: foxes, owls, there is a reduction in the population of not only the lemmings themselves (who die en masse during these same migrations) but also the predators that feed on lemmings, and some of them even migrate with them.

B – contour passing through vertices 2, 4,

And in addition, we offer you an educational video about the importance of food chains in biology.

Target: expand knowledge about biotic environmental factors.

Equipment: herbarium plants, stuffed chordates (fish, amphibians, reptiles, birds, mammals), collections of insects, wet preparations of animals, illustrations of various plants and animals.

Progress:

1. Use the equipment and make two power circuits. Remember that the chain always starts with a producer and ends with a reducer.

Plants → insects→lizard → bacteria

Plants → grasshopper→ frog → bacteria

Remember your observations in nature and make two food chains. Label producers, consumers (1st and 2nd orders), decomposers.

Violet → Springtails→predatory mites→predatory centipedes→ bacteria

Producer - consumer1 - consumer2 - consumer2 - decomposer

Cabbage→ slug→ frog →bacteria

Producer – consumer1 - consumer2 - decomposer

What is a food chain and what underlies it? What determines the stability of a biocenosis? State your conclusion.

Conclusion:

Food (trophic) chain- a series of species of plants, animals, fungi and microorganisms that are connected to each other by the relationship: food - consumer (a sequence of organisms in which a gradual transfer of matter and energy occurs from source to consumer). Organisms of the next link eat the organisms of the previous link, and thus a chain transfer of energy and matter occurs, which underlies the cycle of substances in nature. With each transfer from link to link, a large part (up to 80-90%) of the potential energy is lost, dissipated in the form of heat. For this reason, the number of links (types) in the food chain is limited and usually does not exceed 4-5. The stability of a biocenosis is determined by the diversity of its species composition. Producers- organisms capable of synthesizing organic substances from inorganic ones, that is, all autotrophs. Consumers- heterotrophs, organisms that consume ready-made organic substances created by autotrophs (producers). Unlike decomposers

, consumers are not able to decompose organic substances into inorganic ones. Decomposers- microorganisms (bacteria and fungi) that destroy dead remains of living beings, turning them into inorganic and simple organic compounds.

3. Name the organisms that should be in the missing place in the following food chains.

1) Spider, fox

2) tree-eater-caterpillar, snake-hawk

3) caterpillar

4. From the proposed list of living organisms, create a trophic network:

grass, berry bush, fly, tit, frog, snake, hare, wolf, rotting bacteria, mosquito, grasshopper. Indicate the amount of energy that moves from one level to another.

1. Grass (100%) - grasshopper (10%) - frog (1%) - snake (0.1%) - rotting bacteria (0.01%).

2. Shrub (100%) - hare (10%) - wolf (1%) - rotting bacteria (0.1%).

3. Grass (100%) - fly (10%) - tit (1%) - wolf (0.1%) - rotting bacteria (0.01%).

4. Grass (100%) - mosquito (10%) - frog (1%) - snake (0.1%) - rotting bacteria (0.01%).

5. Knowing the rule for the transfer of energy from one trophic level to another (about 10%), build a pyramid of biomass for the third food chain (task 1). Plant biomass is 40 tons.

Grass (40 tons) -- grasshopper (4 tons) -- sparrow (0.4 tons) -- fox (0.04).

6. Conclusion: what do the rules of ecological pyramids reflect?

The rule of ecological pyramids very conditionally conveys the pattern of energy transfer from one level of nutrition to the next in the food chain. These graphic models were first developed by Charles Elton in 1927. According to this pattern, the total mass of plants should be an order of magnitude greater than that of herbivorous animals, and the total mass of herbivorous animals should be an order of magnitude greater than that of first-level predators, etc. to the very end of the food chain.

Laboratory work No. 1

TROPHIC CHAINS

Purpose of work: obtaining skills in compiling and analyzing food (trophic) chains.

General information

There are various connections between living organisms in ecosystems. One of the central connections, which cements a variety of organisms into one ecosystem, is food, or trophic. Food connections unite organisms with each other according to the food-consumer principle. This leads to the emergence of food or trophic chains. Within an ecosystem, energy-containing substances are created by autotrophic organisms and serve as food for heterotrophs. Food connections are mechanisms for transferring energy from one organism to another. A typical example is an animal eating plants. This animal, in turn, can be eaten by another animal. Energy transfer can occur in this way through a number of organisms.

Each subsequent one feeds on the previous one, which supplies it with raw materials and energy.

This sequence of transfer of food energy in the process of nutrition from its source through a successive series of living organisms is called food (trophic) chain, or power circuit. Trophic chains- this is the path of unidirectional flow of solar energy absorbed during the process of photosynthesis through living organisms of the ecosystem into the environment, where the unused part of it is dissipated in the form of low-temperature thermal energy.

mice, sparrows, pigeons. Sometimes in ecological literature any food connection is called a “predator-prey” connection, meaning that a predator is an eater. The stability of the predator-prey system is ensured by the following factors:

- ineffectiveness of the predator, flight of the prey;

- environmental restrictions imposed by the external environment on population size;

- availability of alternative food resources for predators;

- reducing the delay in the predator's reaction.

The location of each link in the food chain is trophic level. The first trophic level is occupied by autotrophs, or so-called primary producers. Organisms of the second trophic level are called primary

primary consumers, the third - secondary consumers, etc.

Trophic chains are divided into two main types: grazing (grazing chains, consumption chains) and detrital (decomposition chains).

Plant → hare → wolf Producer → herbivore → carnivore

The following food chains are also widespread:

Plant material (eg nectar) → fly → spider → shrew → owl.

Rosebush sap → aphid → ladybug → spider → insectivorous bird → bird of prey.

In aquatic, particularly marine, ecosystems, predator food chains are longer than in terrestrial ones.

The detrital chain begins with dead organic matter - detritus, which is destroyed by detritivores eaten by small predators, and ends with the work of decomposers that mineralize organic remains. Deciduous forests play an important role in the detrital food chains of terrestrial ecosystems, most of the foliage of which is not consumed by herbivores and is part of the forest litter. The leaves are crushed by numerous detritivores (fungi, bacteria, insects), then ingested by earthworms, which uniformly distribute humus in the surface layer of soil, forming a mull. Decomposing

microorganisms completing the chain produce the final mineralization of dead organic residues (Fig. 1).

In general, typical detritus chains of our forests can be represented as follows:

leaf litter → earthworm → blackbird → sparrowhawk;

dead animal → carrion fly larvae → grass frog → grass snake.

Rice. 1. Detrital food chain (according to Nebel, 1993)

As an example, we can consider wood as a source of organic material that is subjected to biological processing in the soil by organisms inhabiting the soil. Wood that falls on the soil surface is primarily processed by the larvae of longhorned beetles, borers, and borers, which use it for food. They are replaced by mushrooms, the mycelium of which primarily settles in the passages made in the wood by insects. Mushrooms further loosen and destroy the wood. Such loose wood and the mycelium itself turn out to be food for fireflower larvae. At the next stage, ants settle in the already severely damaged wood, destroying almost all the larvae and creating conditions for a new generation of fungi to settle in the wood. Snails begin to feed on such mushrooms. Decomposer microbes complete the destruction and humification of wood.

Similarly, there is humification and mineralization of manure from wild and domestic animals entering the soil.

As a rule, the food of every living creature is more or less varied. Only all green plants “feed” the same way: carbon dioxide and ions of mineral salts. In animals, cases of narrow specialization of nutrition are quite rare. As a result of a possible change in animal nutrition, all ecosystem organisms are involved in a complex network of food relationships. Food chains are closely intertwined with each other forming food or trophic networks. In a food web, each species is directly or indirectly connected to many. An example of a trophic network with the placement of organisms by trophic levels is shown in Fig. 2.

Food webs in ecosystems are very complex, and we can conclude that the energy entering them migrates for a long time from one organism to another.

Rice. 2. Trophic network

In biocenoses, food connections play a dual role. Firstly, they

provide the transfer of matter and energy from one organism to another.

Thus, species coexist together and support each other’s life. Secondly, food connections serve as a mechanism for regulating numerical

Representation of trophic networks can be traditional (Fig. 2) or using directed graphs (digraphs).

A geometrically oriented graph can be represented as a set of vertices, denoted by circles with vertex numbers, and arcs connecting these vertices. An arc specifies the direction from one vertex to another. A path in a graph is a finite sequence of arcs in which the beginning of each subsequent arc coincides with the end of the previous one. An arc can be designated by the pair of vertices that it connects. A path is written as a sequence of vertices through which it passes. A path is called a path whose starting vertex coincides with the ending vertex.

FOR EXAMPLE:

AT 3;

1, 2 or 1, 3, 2 – paths from the top

		to the top

In the power network, the top of the graph displays modeling objects; arcs, indicated by arrows, lead from prey to predator.

Any living organism occupies a certain ecological niche. An ecological niche is a set of territorial and functional characteristics of a habitat that meet the requirements of a given species. No two species have identical niches in ecological phase space. According to Gause's principle of competitive exclusion, two species with similar ecological requirements cannot occupy the same ecological niche for a long time. These species compete, and one of them displaces the other. Based on power networks, you can build competition graph. Living organisms in the competition graph are displayed as vertices of the graph; an edge is drawn between the vertices (a connection without direction) if there is a living organism that serves as food for the organisms displayed by the above vertices.

The development of a competition graph allows us to identify competing species of organisms and analyze the functioning of the ecosystem and its vulnerability.

The principle of matching the growth in complexity of an ecosystem with increasing its stability is widely accepted. If the ecosystem is represented by a food network, different ways of measuring complexity can be used:

- determine the number of arcs;

- find the ratio of the number of arcs to the number of vertices;

Trophic level is also used to measure the complexity and diversity of the food web, i.e. the place of the organism in the food chain. The trophic level can be determined both by the shortest and by the longest food chain from the vertex in question, which has a trophic level equal to “1”.

PROCEDURE FOR PERFORMANCE OF THE WORK

Exercise 1

Make a network for 5 participants: grass, birds, insects, hares, foxes.

Task 2

Establish the food chains and trophic level along the shortest and longest path of the food network from task “1”.

		Trophic level and food chain
power supply network	along the shortest path		along the longest path

4 . Insects

Note: The grazing food chain begins with the producers. The organism listed in column 1 is the top trophic level. For consumers of the first order, the long and short paths of the trophic chain coincide.

Task 3

Propose a trophic network according to the task option (Table 1P) and make a table of trophic levels along the longest and shortest path. The food preferences of consumers are shown in table. 2P.

Task 4

Make a trophic network according to Fig. 3 and place its members according to trophic levels

REPORT PLAN

1. Purpose of the work.

2. Food web graph and competition graph based on the training example (tasks 1, 2).

3. Table of trophic levels based on the educational example (task 3).

4. Food network graph, competition graph, table of trophic levels according to the assignment option.

5. Scheme of the trophic network with the placement of organisms by trophic levels (according to Fig. 3).

Rice. 3. Tundra biocenosis.

First row: small passerines, various dipterous insects, ruffed buzzard. Second row: arctic fox, lemmings, polar owl. Third row: white partridge, white hares. Fourth row: goose, wolf, reindeer.

Literature

1. Reimers N.F. Nature management: Dictionary-reference book. – M.: Mysl, 1990. 637 p.

2. Animal life in 7 volumes. M.: Education, 1983-1989.

3. Zlobin Yu.A. General ecology. Kyiv: Naukova Dumka, 1998. – 430 p.

4. Stepanovskikh A.S. Ecology: Textbook for universities. – M.: UNITIDANA,

5. Nebel B. Environmental science: how the world works. – M.: Mir, 1993.

–t.1 – 424 p.

6. Ecology: Textbook for technical universities / L.I. Tsvetkova, M.I. Alekseev, etc.; Ed. L.I. Tsvetkova.–M.: ASV; St. Petersburg: Khimizdat, 2001.-552 p.

7. Girusov E.V. and others. Ecology and economics of environmental management: Textbook for universities / Ed. Prof. E.V. Girusova. – M.: Law and Law, UNITY,

		Table 1P
		Species structure of biocenosis
	Name bio-	Species composition of the biocenosis

	Cedarwood	Korean cedar, yellow birch, variegated hazel,
		sedge, white hare, flying squirrel, common squirrel,
		wolf, brown bear, Himalayan bear, sable,
		mouse, nutcracker, woodpecker, fern.
	Waterlogged	Sedges, iris, common reed. A wolf, a fox come in,
		brown bear, roe deer, mouse. Amphibians – Siberian salamander
	reed grass	sky, Far Eastern tree frog, Siberian frog. Ulit-
		ka, earthworm. Birds – Far Eastern White
		stork, piebald harrier, pheasant, red-crowned crane, white-naped beetle
		Ravl. Swallowtail butterflies.
	White birch	Aspen, flat-leaved birch (white) aspen, alder, dio-
		rather nipponica (herbaceous vine), grasses, sedges,
		forbs (clover, rank). Shrubs – Lespedeza, Rya-
		binnik, meadowsweet. Mushrooms – boletus, boletus.
		Animals - raccoon dog, wolf, fox, bear
		ry, weasel, wapiti, roe deer, Siberian salamander, frog-
		ka Siberian mouse. Birds – great spotted eagle, tit,

	Spruce grass-	Plants – fir, larch, Korean cedar, maple, rowan
		mountain ash, honeysuckle, spruce, sedges, cereals.
	shrubby	Animals – white hare, common squirrel, flying squirrel
		ha, wolf, brown bear, Himalayan bear, sable,
		harza, lynx, wapiti, elk, hazel grouse, owl, mouse, butterfly

		Plants - Mongolian oak, aspen, birch,
		linden, elm, maakia (the only one in the Far East
		tree belonging to the legume family), shrubs –
		lespedeza, viburnum, mountain ash, wild rose,
		herbs – lily of the valley, sedge, hellebore, wild garlic, bells,
		bells. Animals – chipmunk, raccoon dog
		ka, wolf, fox, brown bear, badger, weasel, lynx, ka-
		ban, wapiti, roe deer, hare, Siberian salamander, tree frog
		Far Eastern, Siberian frog, mouse, lizard
		hawk, jay, woodpecker, nuthatch, woodcutter beetle, blacksmith

		Plants - aspen, birch, hawthorn, shi-
		povnik, spirea, peony, cereals. Animals – raccoon
		dog, wolf, fox, brown bear, weasel, wapiti, co-
		sulya, Siberian salamander, Siberian frog, mouse, lizard
		ritsa viviparous, jay, woodpecker, nuthatch, spotted eagle,
		woodcutter beetle, grasshopper,

		Table 2P
	Nutrition spectrum of some species

Alive organisms		Food cravings - “menu”
	Grass (cereals, sedges); aspen, linden, hazel bark; berries (strawberries)

	Cereal seeds, insects, worms.
Flying squirrel

	and their larvae.
Plants	Consume solar energy and minerals, water,
	oxygen, carbon dioxide.
	Rodents, hares, frogs, lizards, small birds.

Common squirrel	Pine nuts, hazelnuts, acorns, cereal seeds.
	Shrub seeds (Eleutherococcus), berries (lingonberries), insects
	and their larvae.
Insect larvae	Mosquito larvae – algae, bacteria.
wet mosquitoes,	Dragonfly larvae are insects and fish fry.
	Herbal juice.
	Rodents, hares, frogs, lizards.

Steller's sea eagle	Fish, small birds.

Brown bear	Euryphage, prefers animal food: wild boars (pork
	ki), fish (salmon). Berries (raspberries, bird cherry, honeysuckle, pigeons)
	ka), roots.
Himalayan bear	Angelica (bear's pipe), forest berries (lingonberries, raspberries, cherry
	fly, blueberry), honey (wasps, bees), lilies (bulbs), mushrooms,
	nuts, acorns, ant larvae.
Insects	Herbaceous plants, tree leaves.

	Mouse, squirrel, hares, hazel grouse.
	Predator. Hares, squirrels, pigs.
		grass (wintering horsetail), legumes (vetch, china),
		hazel bark, willow bark, birch undergrowth, roots of shrubs (forest
	shina, raspberries).
	Buds of birch, alder, linden; cereals; rowan berries, viburnum; needles fir-
	you, spruce, larches.
	Mouse, chipmunk, hares, fox cubs, snakes (snake), lizard, white
	ka, bat.
	Mice, hares, roe deer, in a flock can kill deer, elk, and wild boar.
Earwig	Predator. Fleas, beetles (small), slugs, earthworms.
Woodcutter beetle	Bark of birch, cedar, linden, maple, larch.
	Plant pollen.
peacock eye
	Mouse, hares, chipmunk, Siberian salamander, crane chicks,
	stork, ducks; Far Eastern tree frog, baby pheasants, worms,
	large insects.
	Bark of hazel, birch, willow, oak, sedge, reed grass, reed; leaves are white
	cuts, willow, oak, hazel.
	Predator. Crustaceans, mosquito larvae.

Tree frog far-		Aquatic invertebrates.

		Grasses (reed grass), sedge, mushrooms, plant residues and soil.
		Plants, fish and their eggs during spawning, insects and their larvae

earthworm		Dead plant debris.
Far Eastern		Snail, tree frog, Siberian frog, fish (loach, sleeper), snakes,
White stork		mice, locusts, passerine chicks.
Japanese crane		Sedge rhizomes, fish, frogs, small rodents, chicks.
Pied harrier		Mouse, small birds (buntings, warblers, sparrows), frogs,
		lizards, large insects.
		Birch, alder, reed buds.
Swallowtail butterflies		Pollen from plants (violets, corydalis).
		Carnivorous, prefers animal food - hares, young
		elk calves, roe deer, deer, wild boars.
Raccoon co-		Rotten fish, birds (larks, fescue birds, warblers).

		Branch food (birch, aspen, willow, hazel; oak, linden leaves),
		acorns, oak bark, algae in shallow waters, three-leaf watch.
		Mosquito, spiders, ants, grasshoppers.

Lizard alive		Insects and their larvae, earthworms.

spotted eagle		Predator. Small mammals, pheasant, mice, hares, foxes,
		birds, fish, rodents.
		Squirrels, chipmunks, birds.
Chipmunk		Seeds of apple tree, rose hip, viburnum, field ash, mountain ash; mushrooms;
		nuts; acorns.
		Roots, earthworms, mice, insects (ants and their larvae).
		Predator. Mice.
		Cereal seeds, nuts.
		Pine nuts, acorns, berries (rowan), apple tree.
		Lumberjack beetles, wood-boring insects.
		Wild boar, hare, roe deer, elk calves, fawns, elk, deer (wounded animals).
Nuthatch		Insects; tree seeds, berries, nuts.
Lemmings		Granivores. Sedges, shiksha, cereals.
		Granivores.
		Predator. Lemmings, chicks of partridges, seagulls.
polar owl		Lemmings, mice, voles, hares, ducks, pheasants, black grouse.

Ptarmigan		Herbivores. Cereal seeds; buds of birch, willow, alder.
		Herbivores, leaves and bark of trees, moss - moss.
White hare		In winter - bark; in summer - berries, mushrooms.
		Herbivores. Sedges, grasses, algae, shoots of aquatic plants.
Reindeer		Resin moss, cereals, berries (cloudberries, cranberries), mice.
		Roe deer, wapiti, sika deer, wild boar.
Daphnia, Cyclops		Unicellular algae.

1. Producers(producers) produce organic substances from inorganic ones. These are plants, as well as photo- and chemosynthetic bacteria.

2. Consumers(consumers) consume finished organic substances.

1st order consumers feed on producers (cow, carp, bee)
2nd order consumers feed on first order consumers (wolf, pike, wasp)
etc.

3. Decomposers(destroyers) destroy (mineralize) organic substances to inorganic ones - bacteria and fungi.

Example of a food chain: cabbage → cabbage white caterpillar → tit → hawk. The arrow in the food chain is directed from the one who is eaten towards the one who eats. The first link of the food chain is the producer, the last is the higher-order consumer or decomposer.

The food chain cannot contain more than 5-6 links, because when moving to each next link, 90% of the energy is lost ( 10% rule, rule of the ecological pyramid). For example, a cow ate 100 kg of grass, but gained weight only by 10 kg, because...
a) she did not digest part of the grass and threw it away with feces
b) some of the digested grass was oxidized to carbon dioxide and water to produce energy.

Each subsequent link in the food chain weighs less than the previous one, so the food chain can be represented as biomass pyramids(at the bottom are producers, there are the most of them, at the very top are consumers of the highest order, there are the fewest of them). In addition to the biomass pyramid, you can build a pyramid of energy, numbers, etc.

Establish a correspondence between the function performed by an organism in a biogeocenosis and the representatives of the kingdom performing this function: 1) plants, 2) bacteria, 3) animals. Write the numbers 1, 2 and 3 in the correct order.
A) the main producers of glucose in the biogeocenosis
B) primary consumers of solar energy
C) mineralize organic matter
D) are consumers of different orders
D) ensure the absorption of nitrogen by plants
E) transfer substances and energy in food chains

Answer

Choose three options. Algae in a reservoir ecosystem constitute the initial link in most food chains, since they
1) accumulate solar energy
2) absorb organic substances
3) capable of chemosynthesis
4) synthesize organic substances from inorganic ones
5) provide energy and organic matter to animals
6) grow throughout life

Answer

Choose one, the most correct option. In a coniferous forest ecosystem, 2nd order consumers include
1) spruce
2) forest mice
3) taiga ticks
4) soil bacteria

Answer

1. Establish the correct sequence of links in the food chain using all named objects
1) ciliate-slipper
2) Bacillus subtilis
3) seagull
4) fish
5) mollusk
6) silt

Answer

2. Establish the correct sequence of links in the food chain using all the named representatives
1) hedgehog
2) field slug
3) eagle
4) plant leaves
5) fox

Answer

3. Place the organisms in the correct order in the decomposition chain (detritus). Write down the corresponding sequence of numbers.
1) small carnivorous predators
2) animal remains
3) insectivores
4) saprophagous beetles

Answer

4. Arrange the organisms in the correct order in the detrital food chain. Write down the corresponding sequence of numbers.
1) mouse
2) honey fungus
3) hawk
4) rotten stump
5) snake

Answer

5. Establish the sequence of organisms in the food chain, starting with the organism that absorbs sunlight. Write down the corresponding sequence of numbers.
1) gypsy moth caterpillar
2) linden
3) common starling
4) sparrowhawk
5) fragrant beetle

Answer

6. Establish the correct sequence of organisms in the food chain.
1) wheat grains
2) red fox
3) bug harmful turtle
4) steppe eagle
5) common quail

Answer

7. Establish the sequence of arrangement of organisms in the food chain. Write down the corresponding sequence of numbers.
1) frog
2) already
3) butterfly
4) meadow plants

Answer

8. Establish the sequence of organisms in the food chain. Write down the corresponding sequence of numbers.
1) fish fry
2) algae
3) perch
4) daphnia

Answer

9. Establish the sequence in which the listed objects should be located in the food chain.
1) cross spider
2) weasel
3) dung fly larva
4) frog
5) manure

Answer

10. Establish the sequence of objects in the food chain of an ecosystem. Write down the corresponding sequence of numbers.
1) marten
2) wolf
3) leaf litter
4) earthworm
5) mole

Answer

Establish a correspondence between the characteristics of organisms and the functional group to which it belongs: 1) producers, 2) decomposers
A) absorb carbon dioxide from the environment
B) synthesize organic substances from inorganic ones
B) include plants, some bacteria
D) feed on ready-made organic substances
D) include saprotrophic bacteria and fungi
E) decompose organic substances into minerals

Answer

1. Choose three correct answers out of six. Write down the numbers under which they are indicated. Producers include
1) pathogenic prokaryotes
2) brown algae
3) phytophages
4) cyanobacteria
5) green algae
6) symbiont mushrooms

Answer

2. Choose three correct answers out of six and write down the numbers under which they are indicated. Producers of biocenoses include
1) penicillium mushroom
2) lactic acid bacterium
3) silver birch
4) white planaria
5) camel thorn
6) sulfur bacteria

Answer

3. Choose three correct answers out of six and write down the numbers under which they are indicated. Producers include
1) freshwater hydra
2) cuckoo flax
3) cyanobacterium
4) champignon
5) ulotrix
6) planaria

Answer

FORMED: Choose three correct answers out of six and write down the numbers under which they are indicated. Producers include
A) yeast

Choose three correct answers out of six and write down the numbers under which they are indicated. In biogeocenosis, heterotrophs, unlike autotrophs,
1) are producers
2) provide a change in ecosystems
3) increase the supply of molecular oxygen in the atmosphere
4) extract organic substances from food
5) convert organic residues into mineral compounds
6) act as consumers or decomposers

Answer

1. Establish a correspondence between ecological groups in the ecosystem and their characteristics: 1) producers, 2) consumers. Write numbers 1 and 2 in the order corresponding to the letters.
A) are autotrophs
B) heterotrophic organisms
C) the main representatives are green plants
D) produce secondary products
D) synthesize organic compounds from inorganic substances

Answer

Establish a correspondence between the characteristics of organisms and functional groups in the ecosystem: 1) consumers, 2) producers, 3) decomposers. Write numbers 1-3 in the order corresponding to the letters.
A) return free nitrogen to the atmosphere
B) form primary production
B) form organic substances as a result of chemosynthesis
D) constitute the second trophic level
D) mineralize organic residues

Answer

1. Establish a correspondence between organisms and functional groups in the ecosystems to which they belong: 1) producers, 2) consumers. Write numbers 1 and 2 in the order corresponding to the letters.
A) naked slug
B) common mole
B) gray toad
D) black polecat
D) kale
E) common cress

Answer

2. Establish a correspondence between organisms and functional groups: 1) producers, 2) consumers. Write numbers 1 and 2 in the order corresponding to the letters.
A) sulfur bacteria
B) field mouse
B) meadow bluegrass
D) honey bee
D) creeping wheatgrass

Answer

Establish the sequence of the main stages of the cycle of substances in the ecosystem, starting with photosynthesis. Write down the corresponding sequence of numbers.
1) destruction and mineralization of organic residues
2) primary synthesis of organic substances from inorganic substances by autotrophs
3) use of organic substances by consumers of the second order
4) use of the energy of chemical bonds by herbivorous animals
5) use of organic substances by consumers of the third order

Answer

1. Establish a correspondence between organisms and their function in the forest ecosystem: 1) producers, 2) consumers, 3) decomposers. Write the numbers 1, 2 and 3 in the correct order.
A) horsetails and ferns
B) molds
C) tinder fungi that live on living trees
D) birds
D) birch and spruce
E) putrefaction bacteria

Answer

2. Establish a correspondence between organisms - inhabitants of the ecosystem and the functional group to which they belong: 1) producers, 2) consumers, 3) decomposers.
A) mosses, ferns
B) toothless and pearl barley
B) spruce, larches
D) molds
D) putrefactive bacteria
E) amoebas and ciliates

Answer

3. Establish a correspondence between organisms and functional groups in the ecosystems to which they belong: 1) producers, 2) consumers, 3) decomposers. Write numbers 1-3 in the order corresponding to the letters.
A) spirogyra
B) sulfur bacteria
B) mukor
D) freshwater hydra
D) kelp
E) putrefaction bacteria

Answer

4. Establish a correspondence between the organism and the functional group to which this organism belongs: 1) producers, 2) consumers, 3) decomposers. Write numbers 1-3 in the order corresponding to the letters.
A) dandelion
B) putrefactive bacterium
B) warty birch
D) grass frog
D) common mole
E) penicillium mold

Answer

5. Establish a correspondence between organisms and functional groups in the ecosystem: 1) producers, 2) consumers, 3) decomposers. Write numbers 1-3 in the order corresponding to the letters.
A) penicillium
B) reindeer
B) common juniper
D) cyanobacterium
D) iron bacteria
E) fieldfare

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated in the table. Which of the following organisms are consumers of finished organic matter in the pine forest community?
1) soil green algae
2) common viper
3) sphagnum moss
4) pine undergrowth
5) black grouse
6) wood mouse

Answer

1. Establish a correspondence between an organism and its membership in a certain functional group: 1) producers, 2) decomposers. Write numbers 1 and 2 in the correct order.
A) red clover
B) chlamydomonas
B) putrefaction bacterium
D) birch
D) kelp
E) soil bacterium

Answer

2. Establish a correspondence between the organism and the trophic level at which it is located in the ecosystem: 1) Producer, 2) Reducer. Write numbers 1 and 2 in the correct order.
A) Sphagnum
B) Aspergillus
B) Laminaria
D) Pine
D) Penicill
E) Putrefactive bacteria

Answer

3. Establish a correspondence between organisms and their functional groups in the ecosystem: 1) producers, 2) decomposers. Write numbers 1 and 2 in the order corresponding to the letters.
A) sulfur bacteria
B) cyanobacterium
B) fermentation bacterium
D) soil bacterium
D) mukor
E) kelp

Answer

Choose three options. What is the role of bacteria and fungi in the ecosystem?
1) convert organic substances of organisms into minerals
2) ensure the closure of the circulation of substances and energy conversion
3) form primary production in the ecosystem
4) serve as the first link in the food chain
5) form inorganic substances available to plants
6) are consumers of the second order

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. What role do decomposers play in an ecosystem?
1) form primary organic matter
2) consume detritus
3) serve as food for predator plants
4) release soluble mineral salts into the medium
5) serve as the initial link in the pasture food chain
6) ensure the closure of the cycle of substances

Answer

1. Establish a correspondence between a group of plants or animals and its role in the pond ecosystem: 1) producers, 2) consumers. Write numbers 1 and 2 in the correct order.
A) coastal vegetation
B) fish
B) amphibian larvae
D) phytoplankton
D) bottom plants
E) shellfish

Answer

2. Establish a correspondence between the inhabitants of the terrestrial ecosystem and the functional group to which they belong: 1) consumers, 2) producers. Write numbers 1 and 2 in the order corresponding to the letters.
A) alder
B) typograph beetle
B) elm
D) sorrel
D) crossbill
E) forty

Answer

3. Establish a correspondence between the organism and the functional group of the biocenosis to which it belongs: 1) producers, 2) consumers. Write numbers 1 and 2 in the order corresponding to the letters.
A) tinder fungus
B) creeping wheatgrass
B) sulfur bacteria
D) Vibrio cholerae
D) ciliate-slipper
E) malarial plasmodium

Answer

4. Establish a correspondence between the examples and ecological groups in the food chain: 1) producers, 2) consumers. Write numbers 1 and 2 in the order corresponding to the letters.
A) hare
B) wheat
B) earthworm
D) tit
D) kelp
E) small pond snail

Answer

1. Establish a correspondence between animals and their roles in the biogeocenosis of the taiga: 1) consumer of the 1st order, 2) consumer of the 2nd order. Write numbers 1 and 2 in the correct order.
A) nutcracker
B) goshawk
B) common fox
D) red deer
D) brown hare
E) common wolf

Answer

2. Establish a correspondence between the animal and its role in the savanna: 1) consumer of the first order, 2) consumer of the second order. Write numbers 1 and 2 in the order corresponding to the letters.
A) antelope
B) lion
B) cheetah
D) rhinoceros
D) ostrich
E) neck

Answer

3. Establish a correspondence between organisms and the functional groups of the ecosystem to which they belong: 1) consumer of the 1st order, 2) consumer of the 2nd order. Write numbers 1 and 2 in the order corresponding to the letters.
A) river beaver
B) wild rabbit
B) slug
D) lake frog
D) fur seals

Answer

4. Establish a correspondence between organisms and functional groups in the ecosystem: 1) consumer of the first order, 2) consumer of the second order. Write numbers 1 and 2 in the order corresponding to the letters.
A) Central Asian locust
B) taiga tick
B) dragonfly rocker
D) Colorado potato beetle
D) honey bee
E) ladybug

Answer

Establish a correspondence between the characteristics of organisms and the functional group to which they belong: 1) Producers, 2) Decomposers. Write numbers 1 and 2 in the correct order.
A) Is the first link in the food chain
B) Synthesize organic substances from inorganic ones
B) Use the energy of sunlight
D) They feed on ready-made organic substances
D) Return minerals to ecosystems
E) Decompose organic substances into minerals

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. In the biological cycle occurs:
1) decomposition of producers by consumers
2) synthesis of organic substances from inorganic by producers
3) decomposition of consumers by decomposers
4) consumption of finished organic substances by producers
5) nutrition of producers by consumers
6) consumption of finished organic substances by consumers

Answer

1. Select organisms that are decomposers. Three correct answers out of six and write down the numbers under which they are indicated.
1) penicillium
2) ergot
3) putrefactive bacteria
4) mukor
5) nodule bacteria
6) sulfur bacteria

Answer

2. Choose three correct answers out of six and write down the numbers under which they are indicated. Decomposers in an ecosystem include
1) rotting bacteria
2) mushrooms
3) nodule bacteria
4) freshwater crustaceans
5) saprophytic bacteria
6) chafers

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. Which of the following organisms are involved in the decomposition of organic residues to mineral ones?
1) saprotrophic bacteria
2) mole
3) penicillium
4) chlamydomonas
5) white hare
6) mukor

Answer

Choose one, the most correct option. What do fungi and bacteria have in common?
1) the presence of cytoplasm with organelles and a nucleus with chromosomes
2) asexual reproduction using spores
3) their destruction of organic substances to inorganic ones
4) existence in the form of unicellular and multicellular organisms

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. In a mixed forest ecosystem, the first trophic level is occupied by
1) granivorous mammals
2) warty birch
3) black grouse
4) gray alder
5) angustifolia fireweed
6) dragonfly rocker

Answer

1. Choose three correct answers out of six and write down the numbers under which they are indicated. The second trophic level in a mixed forest ecosystem is occupied by
1) moose and roe deer
2) hares and mice
3) bullfinches and crossbills
4) nuthatches and tits
5) foxes and wolves
6) hedgehogs and moles

Answer

2. Choose three correct answers out of six and write down the numbers under which they are indicated. The second trophic level of the ecosystem includes
1) Russian muskrat
2) black grouse
3) cuckoo flax
4) reindeer
5) European marten
6) field mouse

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. In food chains, first-order consumers are
1) echidna
2) locusts
3) dragonfly
4) fox
5) moose
6) sloth

Answer

Analyze the table “Trophic levels in the food chain.” For each lettered cell, select the appropriate term from the list provided. Write down the selected numbers in the order corresponding to the letters.
1) secondary predators
2) first level
3) saprotrophic bacteria
4) decomposers
5) second-order consumers
6) second level
7) producers
8) tertiary predators

Answer

Analyze the table “Trophic levels in the food chain.” Fill in the blank cells of the table using the terms in the list. For each lettered cell, select the appropriate term from the list provided. Write down the selected numbers in the order corresponding to the letters.
List of terms:
1) primary predators
2) first level
3) saprotrophic bacteria
4) decomposers
5) consumers of the first order
6) heterotrophs
7) third level
8) secondary predators

Answer

Analyze the table “Functional groups of organisms in an ecosystem.” For each lettered cell, select the appropriate term from the list provided. Write down the selected numbers in the order corresponding to the letters.
1) viruses
2) eukaryotes
3) saprotrophic bacteria
4) producers
5) algae
6) heterotrophs
7) bacteria
8) mixotrophs

Answer

Look at the picture of a food chain and indicate (A) the type of food chain, (B) the producer, and (C) the second-order consumer. For each lettered cell, select the appropriate term from the list provided. Write down the selected numbers in the order corresponding to the letters.
1) detrital
2) Canadian pondweed
3) osprey
4) pasture
5) big pond snail
6) green frog

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. Decomposers in the forest ecosystem participate in the cycle of substances and energy transformations, since
1) synthesize organic substances from minerals
2) release energy contained in organic residues
3) accumulate solar energy
4) decompose organic matter
5) promote the formation of humus
6) enter into symbiosis with consumers

Answer

Choose three options. In a forest ecosystem, frogs are considered consumers, since they
1) consume ready-made organic substances
2) participate in the decomposition of organic residues
3) feed on insects
4) have a patronizing connotation
5) constitute the third trophic level
6) synthesize organic substances from inorganic ones

Answer

Choose two correct answers out of five and write down the numbers under which they are indicated. Environmental terms include
1) heterosis
2) population
3) outbreeding
4) consumer
5) divergence

Answer

Choose three correct answers out of six and write down the numbers under which they are indicated. Which of the following animals can be classified as consumers of the second order?
1) gray rat
2) Colorado potato beetle
3) dysenteric amoeba
4) grape snail
5) ladybug
6) honey bee

Answer

Establish the sequence of increase in the biomass of organisms in accordance with the rule of the ecological pyramid, starting with the smallest. Write down the corresponding sequence of numbers.
1) squid, octopus
2) polar bear
3) plankton
4) crustaceans
5) pinnipeds

Answer

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