Exercises

I. Reading comprehension

1. What is the main idea of the article?

a. No living organism exists or can exist as an entity unto itself.

b. Sustainability of human society will depend on maintaining the integrity of the biosphere.

с The entire biosphere is really one mammoth ecosystem.

2. What is said about the Earth in paragraph 1 ?

a. It is a sphere in the void of space.

b. It is unique among all the planets, с It has an oxygen-rich atmosphere.

3. According to paragraph 2, what does the word "species" refer to?

a. Air, water, and nutritive elements from the earth's minerals.

b. The total population of a specific kind of plant, animal or mi­ crobe.

с Plants, animals, and microbes.

4. According to paragraph 3, some prices to be paid for use, misuse, or pollution of natural resources are:

a. potential global warming

b. mutually supportive interrelationships among all living organisms с depletion of the ozone shield

5. In paragraph 4, an ecosystem is defined as:

a. temperature, precipitation, amount of moisture, and all other chemical and physical factors

b. a very condensed description of what is observed in nature

с a grouping of various species of plants, animals, and microbes interacting with each other and with their environment

6. Which paragraph gives a quick tour across the United States?

a. Paragraph 4.

b. Paragraph5. с Paragraph 6.

7. How is each ecosystem characterized in paragraph 6?

a. By grouping of particular plants.

b. By a particular array of animals, с By distinctive plant community.

30 Unit Three _Ec0systems: What They Are 31

8. According to paragraph 7, the following may be considered as an ecosystem:

a. a patch of woods, an open field

b. distinctive grouping of organisms с a pond, a stream

9. Ecotones may be studied as:

a. ecosystems in their own right

b. some animal species с migratory birds

10. Different areas of oceans may be studied as:

a. conspicuous ecotones between ocean and freshwater systems

b. the land in the form of beaches, wet lands and rocky coastlines с separate ecosystems

11. According to paragraph 10, аИ ecosystems and biomes are inter­ connected through:

a. the entire biosphere

b. one mammoth ecosystem

с the movement of air (wind) and water

II. Vocabulary

From the list of words and expressions below, choose the correct word or expression for each blank space. Use each word or expression only once.

marshy area lake

dry land grasslands forests

nutritive ele­ments

amount of moisture open field

bottom

lithosphere wildlife entity sediments soil quality layer

precipitation hydrosphere biosphere plant community array of animals patch of woods

chemical and physi­cal factors stream pond nutrients

(atmosphere), water

around the Earth where

) interact with living things is called

1. The_

( ), and minerals (

the

unto itself.

2. No living organism exists or can exist as an

2. All species depend on air, water and from the earth's min­erals.

2. All organisms help to support and maintain air, water, and . •

Our very term "natural resources" implies that all these things -

air, water, soil, minerals, , __, - are there simply

for our taking.

to which organisms are exposed.

_ supports a particular .

For instance, a , an _, a , a

The environment includes temperature, , , and all

other _ Each

_, each may be

considered and studied as an ecosystem.

9. Consider a , which often occurs between open water of a

and .

10. Oceans include a variety of environments depending on tempera­ ture, water depth, nature of the , and concentrations of

and .