The transfer of energy by living organisms eating each other is called a food chain. These are specific relationships between plants, fungi, animals, and microorganisms that ensure the circulation of substances in nature. Also called a food chain.

Structure

All organisms feed, i.e. receive energy that powers life processes. system trophic chain form links. A link in the food chain is a group of living organisms connected to a neighboring group through the “food-consumer” relationship. Some organisms are food for other organisms, which in turn are also food for a third group of organisms.
There are three types of links:

• producers - autotrophs;
• consumers - heterotrophs;
• decomposers (destructors) - saprotrophs.

Rice. 1. Links in the food chain.

All three links form one chain. There can be several consumers (consumers of the first, second order, etc.). The basis of the chain can be producers or decomposers.

Producers include plants that transform organic substances with the help of light into organic substances, which, when eaten by plants, enter the body of the first-order consumer. The main characteristic of the consumer is heterotrophy. At the same time, consumers can consume both living organisms and dead ones (carrion).
Examples of consumers:

• herbivores - hare, cow, mouse;
• predators - leopard, owl, walrus;
• scavengers - vulture, Tasmanian devil, jackal.

Some consumers, including humans, occupy an intermediate position, being omnivores. Such animals can act as consumers of the first, second and even third order. For example, a bear eats berries and small rodents, i.e. is simultaneously a consumer of the first and second orders.

Reducers include:

• mushrooms;
• bacteria;
• protozoa;
• worms;
• insect larvae.

Rice. 2. Decomposers.

Decomposers feed on the remains of living organisms and their metabolic products, returning inorganic substances to the soil that producers consume.

Species

Food chains can be of two types:

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• pasture (grazing chain);
• detrital (decomposition chain).

Pasture chains are characteristic of meadows, fields, seas, and reservoirs. The beginning of the grazing chain is autotrophic organisms - photosynthetic plants.
Next, the chain links are arranged as follows:

• consumers of the first order are herbivores;
• second-order consumers are predators;
• third-order consumers are larger predators;
• decomposers.

In marine and oceanic ecosystems, grazing chains are longer than on land. They may include up to five consumer orders. The basis of marine chains is photosynthetic phytoplankton.
The following links are formed by several consumers:

• zooplankton (crustaceans);
• small fish (sprats);
• large predatory fish(herring);
• large carnivorous mammals(seals);
• apex predators (killer whales);
• decomposers.

Detritus chains are characteristic of forests and savannas. The chain begins with decomposers that feed on organic remains (detritus) and are called detriophages. These include microorganisms, insects, and worms. All these living organisms become food for top predators, for example, birds, hedgehogs, and lizards.

Examples of two types of food chains:

• pasture : clover - hare - fox - microorganisms;
• detrital : detritus - fly larvae - frog - snake - hawk - microorganisms.

Rice. 3. Example of a food chain.

The top of the food chain is always occupied by a predator, which is a consumer last order in its area. The number of top predators is not regulated by other predators and depends only on external environmental factors. Examples are killer whales, monitor lizards, and large sharks.

What have we learned?

We found out what food chains there are in nature and how the links are located in them. All living organisms on Earth are interconnected food chains, through which energy is transmitted. Autotrophs produce themselves nutrients and are food for heterotrophs, which, when dying, become a breeding ground for saprotrophs. Decomposers can also become food for consumers and produce a nutrient medium for producers without interrupting the food chain.

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Objective of the lesson: To form knowledge about the constituent components of a biological community, about the features of the trophic structure of the community, about food connections that reflect the path of substance circulation, to form the concepts of food chain, food web.

Lesson progress

1. Organizational moment.

2. Checking and updating knowledge on the topic “Composition and structure of the community.”

On the board: Our world is not an accident, not chaos - there is a system in everything.

Question. What system in living nature is this statement talking about?

Working with terms.

Exercise. Fill in the missing words.

Community of organisms different types closely interconnected are called …………. . It consists of: plants, animals, …………. , …………. . A collection of living organisms and components inanimate nature, united by the exchange of matter and energy on a homogeneous area of ​​the earth's surface are called …………….. or ………………….

Exercise. Select four components of the ecosystem: bacteria, animals, consumers, fungi, abiotic component, climate, decomposers, plants, producers, water.

Question. How are living organisms connected to each other in an ecosystem?

3. Studying new material. Explain using presentation.

4. Consolidation of new material.

Task No. 1. Slide No. 20.

Identify and label: producers, consumers and decomposers. Compare power circuits and establish similarities between them. (at the beginning of each chain there is plant food, then there is a herbivore, and at the end there is a predatory animal). Name the way plants and animals feed. (plants are autotrophs, i.e. they produce organic matter themselves, animals – heterotrophs – consume finished organic matter).

Conclusion: power circuit- a series of organisms that feed on each other in succession. Food chains begin with autotrophs - green plants.

Task No. 2. Compare two food chains, identify similarities and differences.

1. Clover - rabbit - wolf
2. Plant litter - earthworm - blackbird - hawk - sparrowhawk (The first food chain begins with producers - living plants, the second with plant residues - dead organic matter).

In nature, there are two main types of food chains: pasture (grazing chains), which begin with producers, detrital (decomposition chains), which begin with plant and animal residues, animal excrement.

Conclusion: Therefore, the first food chain is pasture, because begins with producers, the second is detrital, because starts with dead organic matter.

All components of food chains are distributed into trophic levels. The trophic level is a link in the food chain.

Task No. 3. Make a food chain, including the following organisms: caterpillar, cuckoo, tree with leaves, buzzard, soil bacteria. Indicate producers, consumers, decomposers. (tree with leaves - caterpillar - cuckoo - buzzard - soil bacteria). Determine how many trophic levels this food chain contains (this chain consists of five links, therefore there are five trophic levels). Determine which organisms are located at each trophic level. Draw a conclusion.

• The first trophic level is green plants (producers),
• Second trophic level – herbivores (consumers of the 1st order)
• Third trophic level – small predators (2nd order consumers)
• Fourth trophic level – large predators (3rd order consumers)
• Fifth trophic level - organisms that consume dead organic matter - soil bacteria, fungi (decomposers)

In nature, each organism uses not one food source, but several, but in biogeocenoses food chains intertwine and form food web. For any community, you can draw up a diagram of all the food relationships of organisms, and this diagram will have the form of a network (we consider an example of a food network in Fig. 62 in the biology textbook by A.A. Kamensky and others)

5. Implementation of acquired knowledge.

Practical work in groups.

Task No. 1. Solving environmental situations

1. In one of the Canadian reserves, all wolves were destroyed in order to increase the herd of deer. Was it possible to achieve the goal in this way? Explain your answer.

2. Hares live in a certain territory. Of these, there are 100 small hares weighing 2 kg, and 20 of their parents weighing 5 kg. The weight of 1 fox is 10 kg. Find the number of foxes in this forest. How many plants must grow in the forest for hares to grow up?

3. A reservoir with rich vegetation is home to 2000 water rats, each rat consumes 80g of plants per day. How many beavers can this pond feed if a beaver consumes an average of 200 g of plant food per day?

4. Present the disorderly facts in a logically correct sequence (in the form of numbers).

1. Nile perch began to eat a lot of herbivorous fish.

2. Having multiplied greatly, the plants began to rot, poisoning the water.

3. Smoking Nile perch required a lot of wood.

4. In 1960, British colonists released Nile perch into the waters of Lake Victoria, which quickly multiplied and grew, reaching a weight of 40 kg and a length of 1.5 m.

5. Forests on the shores of the lake were intensively cut down - so water erosion of the soil began.

6. Dead zones with poisoned water appeared in the lake.

7. The number of herbivorous fish decreased, and the lake began to be overgrown with aquatic plants.

8. Soil erosion has led to a decrease in the fertility of fields.

9. Poor soils did not produce crops, and the peasants went bankrupt .

6. Self-test of acquired knowledge in the form of a test.

1. Producers of organic substances in the ecosystem

A) producers

B) consumers

B) decomposers

D) predators

2. To which group do microorganisms living in the soil belong?

A) producers

B) consumers of the first order

B) consumers of the second order

D) decomposers

3. Name the animal that should be included in the food chain: grass -> ... -> wolf

B) hawk

4. Identify the correct food chain

A) hedgehog -> plant -> grasshopper -> frog

B) grasshopper -> plant -> hedgehog -> frog

B) plant -> grasshopper -> frog -> hedgehog

D) hedgehog -> frog -> grasshopper -> plant

5. In a coniferous forest ecosystem, 2nd order consumers include

A) common spruce

B) forest mice

B) taiga ticks

D) soil bacteria

6. Plants produce organic substances from inorganic substances, therefore they play a role in food chains

A) final link

B) initial level

B) consumer organisms

D) destructive organisms

7. Bacteria and fungi play the role of:

A) producers of organic substances

B) consumers of organic substances

B) destroyers of organic substances

D) destroyers of inorganic substances

8. Identify the correct food chain

A) hawk -> tit -> insect larvae -> pine

B) pine -> tit -> insect larvae -> hawk

B) pine -> insect larvae -> tit -> hawk

D) insect larvae -> pine -> tit -> hawk

9. Determine which animal should be included in the food chain: cereals -> ? -> already -> kite

A) frog

D) lark

10. Identify the correct food chain

A) seagull -> perch -> fish fry -> algae

B) algae -> seagull -> perch -> fish fry

C) fish fry -> algae -> perch -> seagull

D) algae -> fish fry -> perch -> seagull

11. Continue the food chain: wheat -> mouse -> ...

B) gopher

B) fox

D) triton

7. General conclusions of the lesson.

Answer the questions:

1. How are organisms interconnected in biogeocenosis (food connections)
2. What is a food chain (a series of organisms sequentially feeding on each other)
3. What types of food chains are there (pastoral and detrital chains)
4. What is the name of the link in the food chain (trophic level)
5. What is a food web (intertwined food chains)

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 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) part of the digested grass was oxidized to carbon dioxide and water for 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 in the right 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

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

Answer

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

Answer

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

Establish a correspondence between the characteristics of organisms and the functional group to which it belongs: 1) producers, 2) decomposers
A) absorb from environment carbon dioxide
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 options. Producers include
1) mold- mukor
2) reindeer
3) common juniper
4) wild strawberries
5) field thrush
6) lily of the valley

Answer

2. 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

3. 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

4. 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 5. 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 the characteristics of an organism and its membership in the functional group: 1) producer, 2) consumers. Write numbers 1 and 2 in the correct order.
A) synthesize organic substances from inorganic ones
B) use ready-made organic substances
C) use inorganic substances in the soil
D) herbivores and carnivores
D) accumulate solar energy
E) use animal and plant foods as a source of energy

Answer

2. 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) synthesized from inorganic substances organic compounds

Answer

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

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

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 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

5. 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

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

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

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

Answer

Determine 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

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

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

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

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

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

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

Answer

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

Analyze the table " Trophic levels in the food chain." For each lettered cell, select the corresponding 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

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

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 corresponding 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 corresponding 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 corresponding 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

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

Establish the order 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

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 beetle
3) dysenteric amoeba
4) grape snail
5) ladybug
6) honey bee

Answer

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Who eats what

Make up a food chain that tells about the characters in the song “A grasshopper sat in the grass.”

Animals that eat plant foods are called herbivores. Those animals that eat insects are called insectivores. Larger prey is hunted by predatory animals, or raptors. Insects that eat other insects are also considered predators. Finally, there are omnivores (they eat both plant and animal foods).

What groups can animals be divided into based on their feeding methods? Fill out the chart.

Power circuits

Living things are connected to each other in a food chain. For example: Aspen trees grow in the forest. Hares eat their bark. A hare can be caught and eaten by a wolf. It turns out this food chain: aspen - hare - wolf.

Compose and write down power supply circuits.
a) spider, starling, fly
Answer: fly - spider - starling
b) stork, fly, frog
Answer: fly - frog - stork
c) mouse, grain, owl
Answer: grain - mouse - owl
d) slug, mushroom, frog
Answer: mushroom - slug - frog
e) hawk, chipmunk, cone
Answer: cone - chipmunk - hawk

Read short texts about animals from the book "With Love for Nature." Identify and write down the type of food animals eat.

In autumn, the badger begins to prepare for winter. He eats up and gets very fat. He eats everything he comes across: beetles, slugs, lizards, frogs, mice, and sometimes even small hares. He eats and wild berries, and fruits.
Answer: badger is omnivorous

In winter, the fox catches mice and sometimes partridges under the snow. Sometimes she hunts for hares. But hares run faster than a fox and can run away from it. In winter, foxes come close to human settlements and attack poultry.
Answer: carnivorous fox

At the end of summer and autumn, the squirrel collects mushrooms. She pins them on tree branches so that the mushrooms dry out. The squirrel also stuffs nuts and acorns into hollows and cracks. All this will be useful to her during the winter lack of food.
Answer: squirrel is herbivorous

The wolf is a dangerous beast. In summer he attacks various animals. It also eats mice, frogs, and lizards. Destroys bird nests on the ground, eats eggs, chicks, and birds.
Answer: carnivorous wolf

The bear breaks up rotten stumps and looks for fatty larvae of woodcutter beetles and other insects that feed on wood. He eats everything: he catches frogs, lizards, in a word, whatever he comes across. Digs plant bulbs and tubers from the ground. You can often meet a bear in berry fields, where he greedily eats the berries. Sometimes a hungry bear attacks moose and deer.
Answer: the bear is omnivorous

Based on the texts from the previous assignment, compose and write down several power circuits.

1. strawberry - slug - badger
2. tree bark - hare - fox
3. grain - bird - wolf
4. wood - beetle larvae - woodcutter - bear
5. young shoots of trees - deer - bear

Draw a food chain using the pictures.

For me, nature is a kind of well-oiled machine, in which every detail is provided. It’s amazing how well everything is thought out, and it’s unlikely that a person will ever be able to create something like this.

What does the term "power chain" mean?

According to scientific definition, this concept includes the transfer of energy through a number of organisms, where the producers are the first link. This group includes plants that absorb inorganic substances from which they synthesize nutritious organic compounds. They feed on consumers - organisms that are not capable of independent synthesis, which means they are forced to eat ready-made organic matter. These are herbivores and insects that act as “lunch” for other consumers - predators. As a rule, the chain contains about 4-6 levels, where the closing link is represented by decomposers - organisms that decompose organic matter. In principle, there can be much more links, but there is a natural “limiter”: on average, each link receives little energy from the previous one - up to 10%.

Examples of food chains in a forest community

Forests have their own characteristics, depending on their type. Coniferous forests are not distinguished by rich herbaceous vegetation, which means their food chains will have a certain set of animals. For example, a deer enjoys eating elderberry, but it itself becomes prey for a bear or lynx. The broad-leaved forest will have its own set. For example:

• bark - bark beetles - tit - falcon;
• fly - reptile - ferret - fox;
• seeds and fruits - squirrel - owl;
• plant - beetle - frog - snake - hawk.

It is worth mentioning scavengers who “recycle” organic remains. There are a great variety of them in forests: from the simplest unicellular organisms to vertebrates. Their contribution to nature is enormous, since otherwise the planet would be covered with animal remains. They transform dead bodies into inorganic compounds that plants need, and everything starts anew. In general, nature is perfection itself!