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.

Questions:

1. What are bacteria?

2. Where do bacteria live?

3. How do bacteria differ from each other?

4. What coccus types are there?

5. What bacillus type causes tuberculosis?

6. Why must the food of all bacteria be soluble?

7. What is there in some bacteria?

8. How do bacteria usually reproduce?

 

II. Rewrite and translate in writing paragraphs 2, 3.

III. Put questions to the underlined words.

1. Parasitism involves a close association between a parasite and its host.

2. Glycolysis occurs in the cytoplasm of the cell and the presence of oxygen is unnecessary.

3. In crocodiles the teeth are placed one on top of the other, like the hats of a circus clown.

4. A flowering plant usually produces many seeds.

5. The “Origin of Species” by Charles Darwin was first published in November, 1859.

6. The Middle Ages people believed the Earth to be the centre of the Universe.

 

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

1. There (to be) some protozoa that have no organs of locomotion.

2. Some light energy (to need) for photosynthesis.

3. Francesco Redi (to cover) the tubes with paper, and no maggots and flies (to appear) in them.

4. Biologists (to classify) fishes into two broad groups: cartilaginous or gristly fishes and bony fishes.

5. All living organisms may (to regard) as machines which (to transform) energy from one form into another.

6. I (to know) something about hereditary diseases.

 

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

1. Between the end of May and July nests detected at earlier dates were checked several times.

2. The smallest infectious agents known to researchers are termed subviral infectious agents, or subviruses.

3. The most recent work has shown that prions may be proteins produced somewhat abnormally by infected genes that somehow go awry.