Биология в современном мире. Учебное пособие

2.2 Exercise 2

Mind the following regular verbs.

to share – делить; to occur – происходить, случаться; to consider – считать,

рассматривать; to acquire – приобретать; to reduce – уменьшать; to ensure –

обеспечивать; to remain – оставаться; to receive – получать; to use -

использовать; to interact – взаимодействовать; to obtain - получать; to suffer –

страдать; to avoid – избегать.

2.3 Exercise 3

Give three principle forms of the following irregular verbs. Mind them.

to mean, to give, to catch, to cling, to set, to do, to die, to become, to begin, to learn, to breed.

2.4 Exercise 4

Read and translate the following groups of words. Use a dictionary if necessary.

1)to act – action; interaction between predator and pray.

2)fame – familiar – familiarity – familiarize – familiarly – famous; the most familiar relationships.

3)to relate – related – relation – relational – relationship, relative – relatively

–relativity – interrelation – interrelationship – unrelationship.

4)benefit – beneficient – beneficial; to have obvious benefits to predation.

5)to reduce – reduced – reducable – reduction; to reduce prey population.

6)nutrient – nutriment – nutrition, nutritious – nutritive; to gather nutrients from the rock.

7)harm, harmless, harmful, some relationships can be harmful to one

member.

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8) to reside; residence – residency – resident – residential – residentiary; a temporary resident.

2.5 Exercise 5

Read and translate the following word phrases. Pay attention to the attributes. songbirds living in nearby trees; the weakened sick and aged members of a

population; prey population size; remaining members; available food supply benefit; interaction found in living systems; living and non-living components of the ecosystem, daytime hunting; competition for limited resources; an organism’s niche; habitat requirements; important food sources ; fellow inhabitants; habitat database; the requirements to be met, condors to be released.

2.6 Exercise 6

Choose the proper equivalents to the following verb groups.

Translate the sentences, paying attention to the Subjunctive mood.

1)If you are to describe yourself to a foreigner , you will probably begin with where you live.

2)If you were to describe yourself to a foreigner , you would probably begin with where you live.

3)If you had been to describe yourself to a foreigner last year, you would have probably begin with where you lived.

4)The koala is a specialist that feeds exclusively on eucalyptus leaves, without them it would surely perish.

5)Should a food source disappear, a generalist will not suffer.

6)

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7) If supplies of energy sources should be cut off catastrophe could follow.

2.8 Exercise 8

Translate the sentences into English.

1)Если исчезнет источник питания, то койот не пострадает.

2)Если бы исчез источник питания, то койот не пострадал бы.

3)Если бы ученые разработали базу данных места распространения этого животного три года назад, то этот вид не стал бы вымирающим.

2.9 Exercise 9

Put four types of questions to the following sentences.

1)Predation occurs when one organism kills another for food.

2)Not all species interact in ecosystem.

3)Renewable substitutes must be found to provide energy, building materials and raw materials.

2.10 Exercise 10

Read the following text. Translate it.

Biotic Factors.

The biotic components of an ecosystem are its living things – fungi, plants, animals and microorganisms. Organisms live in populations, groups of the same species occupying a given region. Populations are dynamic groups, changing in size, age, structure and genetic composition in correspondence to changes in the environment. Populations never live alone in an ecosystem. They always share resources with others forming a community. A community is defined as the organisms living within a given area. In Yellowstone National Park in Wyoming and Montana there is a community familiar to many Americans. It consists of grizzly bears, elk, mule deer, coyotes, ravens and many other organisms, including dozens of plants, all forming a complex community of living things.

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Within communities there are many different kinds of relationships – some cooperative, some not. One of the most familiar relationships is the predator-prey interaction. Predation occurs when one organism kills another for food, for instance when a robin catches a worm or a grizzly catches a ground squirrel. Biologists even consider grazing a type of predation. Elk , for example, prey on grass. The interaction between predator and prey has obvious benefits to predators because it is often their chief means of acquiring food. Predation also benefits prey populations because predators often kill the weakened, sick and aged members of a population. This helps reduce prey population size and ensures that the remaining members have a larger share of the available food supply benefit especially evident in winter months when food is in naturally short supply.

Another type of interaction found in living systems is commensalism, a relationship between two species is beneficial to one, but neutral to the other. Humans, for instance, form bacteria in their intestinies. For the most part, these organisms provide little or no benefit (they produce a small amount of vitamin K and a few other vitamins). The bacteria, however benefit enormously by this association receiving an abundant food supply.

Mutualism is a relationship that is beneficial to both organisms. A classic example is lichen, an organism that clings to barren rock, capturing water from rainfall and gathering nutrient from the rock by eating away at its surface. Lichens are fungi that house algae inside them. The algae are photosynthetic. They capture sunlight and produce a whole host of organic molecules used by lichen for energy and growth. The fungi, in turn, provide shelter and moisture. Both organisms benefit from the relationship. Not all species interact in an ecosystem. This «unrelationship» is called neutralism. Seabirds on the coast of Louisiana and Texas, for instance, don’t interact with songbirds living in nearby trees. Some relationships can be harmful to one member. Parasitism is an example. Parasitism occurs when species lives on or even inside the other called the host. In this relationship the parasite obtains food by slowly eating the host or by dining on fluids inside the host. A parasite may be a temporary resident such as a wood tick, or it may set up a long-term relationship as

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tapeworms do. When the host is healthy parasites simply die on the surplus and have little effect. However, parasites can kill a debilitated host that is suffering from diseases, aged and weak or is under considerable stress. The final relationship that is worth noting is competition, a fight for resources between members of the same species (intraspecific) or between members of different species (interspecific). Competition is an extremely important force for it can become a major component of natural selection. When interspecific competition is intense, one species may displace another.

2.11 Exercise 11

Answer the following questions.

1)Living organisms are the biotic components of an ecosystem, aren’t they?

2)What can you say about populations?

3)When does predation occur?

4)What kind of relationship between two species is called commensalism?

5)Is mutualism beneficial for organisms? Why?

6)When does parasitism occur?

7)What does intraspecific (interspecific) competition mean?

2.12 Exercise 12

Write down from the text all the biological terms you came across. Mind them.

2.13 Exercise 13

Write down from the text the names of different animals, plants and birds.

Mind them.

2.14 Exercise 14

Fill in the scheme and retell the text, figure 3.

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Biotic factors

neutralism

Figure 3 - Exercise 14

2.15 Exercise 15

Describe biotic factors (one of them) to your partner. Ask him what he or she knows about it.

2.16 Exercise 16

Read the text, discuss it with your partner. Ask questions, share your opinions, make up your own schemes.

Habitat and Niche.

If you were to describe yourself to a foreigner you would probably begin with where you live. Then you might tell what you do, who your friends (and enemies) are, how you interact with others and what you do in your spare time. If you asked an ecologist studying armadillos to describe them, she would probably follow a similar approach, first telling you where these armored minitanks live and then what they do. Where an organism lives is its habitat. Where it lives and how it fits into the habitat ecosystem are its ecological niche or simply its niche. To describe an organism means to tell what it eats, what eats it , where it lives and how it interacts with other living and non-living components of the ecosystem. This is no easy task.

No two species occupy the same niche, but similar species living in the same habitat often have similar life styles. Consider the red-tailed hawk and the great horned owl. On the surface these species may seem quite similar, may be indentical. Hawks and owls both prey on mice and other rodents. They live in trees. But owls generally live in dense forests and come out at night to feed, whereas hawks prefer

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daytime hunting. Despite their apparent similiarities, therefore, these species occupy slightly different niches. The evolution of species to fit different niches has two beneficial effects: first, it reduces competition for limited resources by members of different species (interspecific competition), second, it makes full use of environmental resources.

Because no two species occupy the same niche, two similar species can coexist in a given habitat without threatening each other’s survival. For example, elk and mule deer live in the same habitat in the Rocky Mountains. But an elk feeds primarily on grasses and herbivorous plants whereas a deer feeds primarily on shrubs.

An organism’s niche may be generalized or specialized. Take the koala of Australia and the coyote of North America as examples. The koala is a specialist that feeds exclusively on eucalyptus leaves. Without them it would surely perish. The coyote, on the other hand, feeds on a wide variety of animals: rodents, rabbits, ground-nesting birds, snakes and an occasional sheep. The coyote occupies a wide range of habitats, too, unlike the koala. Because of its versatility the coyote is considered a generalist. Humans beings, like coyote, are generalists in many ways. We live in diverse climates and eat a wide variety of plants and animals.

Generalists trend to be less subject to changes in the abiotic and biotic environment and, therefore, are less apt to become extinct. Should a food source disappear, a generalist will not suffer. Specialists, on the other hand, walk a tightrope. Their existence may easily be threatened by the loss of a single food supply. Today the giant panda of China is threatened by the loss of its sole food source, the bamboo.

Although humans are generalists, our recent evolutionary history has been marked by increasing specialization. Today, for example, we depend on a handful of metals, a relatively small number of crops and livestock species, and a few energy sources. If supplies of any of these should be cut off, catastrophe could follow. Avoiding such hardship, many experts believe, requires us to build a future less dependent on nonrenewable resources. Almost certainly, renewable substructures must be found to provide energy, building materials and raw materials for the many chemicals we use. To avoid hardship we must also protect our vast biological

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resources, for example, the genetic stock of the tropics from which many of our important cultivated crops once came. We must manage our forests and grasslands well and protect commercial fish species. More than ever we are learning that protecting these biological resources means reducing air and water pollution.

Studying the niches of organisms is of great importance today. It can help science predict the impacts of human action on species and can be used to help save organisms from extinction as well. Knowing the habitat requirements, important food sources and other important facts about an organism’s niche will help society learn to accommodate its fellow inhabitants. Scientists are developing a habitat database that may help them understand the niche of the California condor, a species on the brink of extinction. All condors are in captivity now. Researchers hope to breed them successfully and one day be able to release them into the wild. The database will help scientists find a new suitable habitat that meets their requirements.

2.17 Exercise 17

Summarize the information about the biotic factors and habitats and niches. Make up your plan of the texts and speak on them.

3 Lesson 3. Soil erosion (Эрозия почвы)

3.1 Exercise 1

Mind the following words and set expressions.

1)layer – слой;

2)widespread – широко распространенный;

3)to be due to – быть обусловленным;

4)improper working of the land – неправильная обработка земли;

5)sparse – редкий, разбросанный;

6)vegetation cover – растительный покров;

7)mud streams – грязевые потоки;

8)to take place; to occur– происходить

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9)washout – размыв, смыв;

10)gully – глубокий овраг;

11)to plough – пахать, распахивать;

12)non-turning deep ploughing – прямая глубокая вспашка;

13)in order to – для того, чтобы;

14)retention – удерживание, сохранение;

15)furrow – борозда;

16)to attach importance to smth – придавать значение чему-либо, считать что-либо важным;

17)to subordinate – подчиняться;

18)crop rotation system – система севооборота;

19)matrix – основная масса;

20)fallow land – земля под паром.

3.2 Exercise 2

Mind the following regular verbs.

to destroy – разрушать; to notice – замечать; to suspend – откладывать; to follow – следовать; to restrict – ограничивать; to turn – превращать; to absorb –

поглощать; to protect – защищать; to plant – сажать; to prevent – мешать; to increase –увеличивать; to require – требовать; to secure – гарантировать,

обеспечивать; to resemble – напоминать; to move – двигать; to carry – нести; to raise – поднимать; to restore – восстанавливать; to establish – устанавливать; to plough – пахать; to prevail – преобладать.

3.3 Exercise 3

Give three principle forms of the irregular verbs. Mind them.

to go, to begin, to fight, to run, to grow, to wear, to arise, to blow, to throw, to hit, to fall, to catch, to drive, to break.

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