Questions:

1. How do some lowly animals, like Hydra, spend much of their life?

2. What mode of progression do the vast majority of animals have?

3. Who can carry out complicated series of movements with fore-limbs?

4. What do all movements depend upon?

5. What is a skeleton?

6. What does a skeleton protect?

7. Is the skeleton of all Mammals highly developed?

8. Why must not the skeleton be rigid?

II. Rewrite and translate in writing paragraphs 2, 4, 6.

III. Put questions to the underlined words.

1. The most important building material of the Coral Polyps is lime.

2. Vitamins B and C are soluble in water, and are widely distributed in fresh fruit and vegetables.

3. Scientists placed Fungi and Bacteria in the plant kingdom.

4. We can divide these organisms into 2 groups.

5. These authors received very important results and summarized them in a large publication.

6. Some fish develop great speed in swimming.

IV. Put the verbs in brackets in the right form and voice. Translate the sentences into Russian in writing.

1. There (to be) some water in this mixture.

2. During the second half of the nineteenth century, it (to find) that some diseases (to cause) by very tiny creatures-the bacteria.

3. These scientists (to receive) very important results and (to summarize) them in a large publication in 2007.

4. Some bacteria (to synthesize) complex organic materials using chemical energy.

5. An instrument with a needle that always (to point) north and south (to call) a compass.

6. The longest cells (to be) certain nerve cells which can reach over a metre in length.

V. Translate the following sentences into Russian in writing, pay attention to different forms of adjectives.

1. Human erythrocytes are often used as a mode system, reflecting cellular properties in a simpler way than nucleated cells.

2. The earliest fossils of another ancient group, the cycads, date to about 240 million years ago.

3. The most primitive of the vascular plants are the psilophytes.

VI. Rewrite and translate the following sentences into Russian. Pay attention to the modal verbs.

1. Nevertheless, “hybrides” made between bacterial strains with different characteristics may show characteristics from both parents.

2. All the laboratory vessels have to be carefully washed before using them for any experiments.

3. The development of this disease must have been considerably favoured by high moisture conditions.

4. Every student should know the difference between the leaves of oak and birch.

5. This plant could have grown under such conditions rather well.

VII. Rewrite and translate the following sentences into Russian. Pay attention to different meanings of the words.

1. The weight of all plants is 10000 times greater than that of all animals.

2. It is a plant using large amounts of water at the time of its most intensive growth.

3. One should not forget that temperature plays an especially important role at the time of developing the root system.

4. It is too late to lock the stable-door when the horse has been stolen.

5. This means that there must be harmony among all the genes which a population contains.

VIII. Put in some, any, something, anything, nothing, nobody, anybody and translate the sentences into Russian.

1. We didn’t see ... flowers in the garden.

2. Do you keep on ... diet?

3. We knew ... about crossing-over some ten years ago.

4. Is ... knocking at the door? – No, ... is knocking at the door. You are mistaken.

5. ... light energy is needed for photosynthesis.

IX. Make plural forms of the following nouns.

1. medium –

2. stoma –

3. phylum –

4. sheep –

5. means –

Variant 5

I. Read the text and answer the questions in written form.

Bacteria: their Construction

1. Bacteria are very small single-celled organisms (micro-organisms) that exist in enormous numbers almost everywhere. They live in soil, water, air, and in living and dead animals and plants. A gram of soil can contain up to a thousand million bacteria, and there may be hundreds in a single drop of milk.

2. Bacteria differ from each other mainly in where and on what they live, and in the shape of their single cells. There are the spherical coccus types such as Staphylococcus and Streptococcus, which often occur in chains or masses, and the rod-shaped bacillus type such as Mycobacterium, which causes tuberculosis. Other disease-causing bacteria are Eberthella typhi (typhoid), and Vibrio oholerae (cholera). The type of bacterium which forms a coil on spiral is Spirillum.

3. Although bacteria cells are more complicated than viruses they are still very simple. Their structure has been worked out with optical microscopes which magnify by one hundred thousand times. All bacteria have a tough outer cell wall so their food must be soluble before it can be absorbed into the cell. In some bacteria there is a protecting layer of jelly enclosing the cell wall and also one or more minute fibres (flagella) used for swimming. Inside the cell there is a coil of DNA and other chemical substances, but there is no definite nucleus or any of the other structures found in plant and animal cells.

4. Bacteria usually reproduce by simply splitting in two. When temperature conditions are favourable, about 37⁰С for most bacteria, they can divide about once every 30 minutes. In theory, one bacterium could form about 140 000 000 000 000 bacteria at the end of 24 hours.