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Cells: the Smallest Units of Life, their Structure

 

All living things, except for the very smallest, are made up of many units called cells. Although they basically contain the same structures, cells are very varied in shape, size and function. There are many millions of cells in every human being, all too small to be seen individually without microscope. Sperm cells are particularly small, about five-hundredths of a millimetre long. The very largest cells are birdís eggs, in which most of the bulk is a food store called the yolk.

Each cell contains a nucleus, which looks like a dot under an ordinary microscope and is embedded in a jelly-like mass called the cytoplasm. Using an electron microscope, which gives a greater magnification, various structures (organelles) can be seen in the cytoplasm. Each of these organelles does a special job.

The nucleus controls the shape, size and functions of the cell and it contains the hereditary material. Around the outside of the cell is a very thin membrane called the plasma membrane, which is made of protein and fat. It acts as a sieve, allowing certain chemicals to pass through, while at the same time keeping others out. Within the cell is a complex series of channels bounded by membranes, the endoplasmic reticulum, which acts as a sieve and as a means of transport for substances in the cytoplasm. Another membrane system, the golgi apparatus, secretes substances made by the cell.

Among the most important cell structures in the cytoplasm are mitochondria and ribosomes. The mitochondria are organelles in which the complicated processes of respiration take place; they release the energy that keeps the cell alive. The ribosomes are attached to the endoplasmic reticulum. Ribosomes, which are made of RNA (ribonucleic acid), are very small structures that help to žŗÍŚ proteins - a process controlled by the nucleus. Protein-making is vital for the working of the cell because some proteins are enzymes, the catalysts for all the processes of life (a catalyst is a substance that speeds up a reaction without itself being used up). Nuclei, mitochondria, ribosomes and membranes are found in both animal and plant cells. Some cells contain other structures or materials for doing special jobs. For instance, haemoglobin is found in blood cells, contracting strands in muscle cells and chloroplasts in plant cells.

 

 

CRAMMAR EXERCISES

Ex. 1. Choose the right form of the nouns.

1. All the work was done by one (persons, person). 2. In the first study (years, year) the author's (familiarity, familiarities) with the study area, breeding phenology and with the behaviour of the particular species during the breeding (sŚason, seasons) was poor, but it grew from year to year. 3. This (factors, factor) probably had the greatest (effect, effects) on the accuracy of the (result, results). 4. Our (experiment, experiments) proved that the energy requirements of (erythrocytes, erythrocyte) increase when the (cell, cells) are deformed by mechanical stress. 5. From a practical and logistic standpoint it is important in a transfusion service to be able to store red blood cells in a refrigerator for some (week, weeks). 6. Some external cellular (structures, structure) have basic (functions, function) in the cell metabolism, while others are directed to the environment. 7. The importance of surface structures in phytopathogenic (bacteria, bacterium) is well known. 8. Genetic (basis, bases) of disease resistance can only be analysed with proper quantification of the scoring. 9. It is very unlikely that all the above-mentioned complex (phenomena, phenomenon) are governed by a few major genes rather it seems more convincing that a large number of (gene, genes) are responsible. 10. Another question concerns their possible significance for the assessment of genetic (risk, risks) in (mŚn, man), using the doubling-dose (method, methods).



 

Ex. 2. Translate the sentences into Russian, pay attention to the plural form of the nouns.

1. Of the four analysed heavy metals lead showed the highest toxicity. 2. The concentration of this metal found in the river water was lethal for the alga, while half of this concentration still strongly inhibited growth of the culture. 3. The solutions of normal equations for these functions result in parameters of regression equations and on this basis the estimations of weights were obtained. 4. In dystrophic lakes rich in organic matter the number of bacteria is dearly lower than in eutrophic ones. 5. There is no single minimum and no group of minima which would be significantly lower in energy from the others. 6. Divergent data can be found in the literature concerning the growth of algae in environments with cadmium and sine. 7. All the species under study nested on islands in the river current, although there were in many places structurally convenient habitats on the river banks. 8. This is therefore the most reliable method of retrospective calculation of weights on the basis of mean body length of fish.

 

Ex.5. Correct the mistakes in these sentences using the right numbers.

1. After the game I heard the crowd was over twenty thousands.

2. We arrived on the ten September.

3. There were two hundreds twenty altogether.

4. My birthday is thirty-one August.

5. My phone number is seven twenty three, six nought nine.

 

Ex. 6. Answer these questions. Pay attention to the numbers.

1. When were you born?

2. How much do you weigh?

3. What is the number of the flat or house where you live?

4. Is that an odd or an even number?

5. What is your phone number?

6. What is the approximate population of your town?

7. What is the approximate population of your country?

8. What is the normal temperature of a healthy person?

9. How many kilometers are there in a mile?

 

Ex. 7. Complete the sentences. Use: myself, yourself, yourselves, each other etc.

1. He looked at ... in the mirror.

2. Iím not angry with you. Iím angry with ... .

3. When we go on holiday, we always enjoy ... .

4. Mary and Jane were at school together, but they never see ... now.

5. Many people talk to ... when they are alone.

6. Thereís food in the kitchen. If you and Chris are hungry, you can help ... .

7. Margaret had a nice time in London. She enjoyed ... .

8. He never thinks about other people. He only thinks about ... .

9. I want to know all about you. Tell me about ... . (one person)

10. I picked up a very hot plate and burnt ... .

11. Goodbye! Have a nice holiday and look after ... . (two people)

12. My friends had a nice time in Moscow. They enjoyed ... .

 

Ex. 8. Put in: some, any, no, something, somebody, anything, anybody, nothing, nobody, nowhere, somewhere, anywhere.

1. Iím going to the post office. I need ... stamps.

2. There arenít ... shops in this part of town.

3. Alice and George havenít got ... children.

4. Do you know ... good hotels in London?

5. Have you got ... brothers or sisters?

6. She said ... to me but I didnít understand it.

7. Do you know ... about politics?

8. I went to the shop but I didnít buy ... .

9. ... has broken the window. I donít know who.

10. There isnít ... in the bag. Itís empty.

11. Iím looking for my keys. Has ... seen them?

12. I didnít eat ... because I wasnít hungry.

13. This is a secret. Please donít tell ... .

14. There is ... sugar in your coffee.

15. Do you know where Jane is? No, Iíve got ... idea.

16. The weather was cold but there was ... wind.

17. Everything was correct. There were ... mistakes.

18. They want to go on holiday but theyíve got ... money.

19. She has got ... free time.

20. That house is empty. ... lives there.

21. Jack has a bad memory. He canít remember ... .

22. Iím afraid I canít help you. Thereís ... I can do.

23. I donít know ... about car engines.

24. She spoke very fast. I didnít understand ... .

25. Helen has gone away. ... knows where she is. She didnít tell ... where she was going.

26. Tom lives ... near Moscow.

27. Iím looking for my glasses. I canít find them ... .

28. I donít like cold weather. I want to live ... warm.

29. Iím staying here. Iím not going ... .

30. I donít like this town. There is ... to go.

31. We always go to the same place. Letís go ... different.

32. Whatís that letter? Ė Itís ... important.

33. Why are you standing? Ė Because there isnít ... to sit.

34. All the hotels were full. There was ... to stay.

35. Children need ... to play with.

 

Ex. 9. Put in: there + is/are/was/were/has been/will be.

1. ... a good film on TV yesterday.

2. ... enough space for the museum there.

3. ... 24 hours in a day.

4. How many departments ... at the faculty today?

5. ... a party at the club last Friday but I didnít go.

6. Why are those policemen outside the bank? ... a robbery.

7. When you arrive tomorrow ... somebody at the station to meet you.

8. More than 80 years ago ... 3 departments at the faculty. Now... nine.

9. Last week I went back to the town where I was born. Itís very different now. ... a lot of changes.

10. I think everything will be O.K. I donít think ... any problem.

 

Ex. 10. Put in: it or there.

1. ... rains a lot in writer.

2. ... was a strong wind yesterday.

3. How far is ... from your house to the University.

4. ... was a nice day yesterday.

5. We canít go skiing. ... isnít any snow.

6. ... is hot in this room. Open the window.

7. We didnít visit the museum. ... wasnít enough time.

8. Iím sorry Iím late. ... is a lot of traffic.

9. Is ... a swimming pool at the University?

10. Iíll do my packing today because ... wonít be time tomorrow.

 

Ex.11. Put the adjectives in brackets in the correct form and translate the sentences.

1. When is (long) day of the year?

2. Winter is (cold) season.

3. Moscow is (large) than St. Petersburg.

4. My friendís car is not so (new) as my car.

5. Where is it (beautiful): in the mountains or near the sea?

6. It was (bad) cold Iíve ever had.

7. In spring days are (long) than in winter.

8. It is (cold) today than it was yesterday.

9. The Russian grammar is (difficult) than the English one.

10. It was (good) meal Iíve ever had.

11. The Caucasus are (high) mountains in Europe.

12. Friendship is (strong) than steel.

13. (Long) day has an end.

14. Health is (good) than wealth.

 

Ex.12. Which is right? Translate the sentences. Pay attention to the adjectives and adverbs.

1. Donít eat so quick/ quickly. Itís not good for you

2. You are a good runner. You run fast/ fastly.

3. Can you speak slow/ slowly, please?

4. Bill is a very careful/ carefully driver.

5. Whereís Diane? Ė She was here but she left sudden/ suddenly.

6. Some companies pay their workers very bad/ badly.

7. I met them a long time ago, so I donít remember them very good/ well.

8. She works hard/ hardly.

9. I usually go to bed late/ lately.

10. Donít speak to me so cold/ coldly.

11. You sound happy/ happily.

12. Can you tell me the exact/ exactly time of his arrival?

13. Sorry, but I donít know exact/ exactly when he comes back.

14. They have lived all their life happy/ happily.

15. These flowers smell nice/ nicely.

16. He looks cold/ coldly.

17. I donít want the soup. It tastes horrible/ horribly.

 

Ex.13. Present, Past, Future Simple Tenses in the Active Voice. Use the proper form of the verb, read and translate.

1. My everyday activities (to be) quite routine.

2. They not (to differ) from those of any other working person.

3. My working day (to begin) at 7 a.m.

4. For breakfast I usually (to have) fried eggs, tea or coffee.

5. It (to take) me 20 minutes to get to my hospital by bus.

6. At 8:30 a.m. I (to take) up my duties at the hospital for the duration of 24 hours.

7. It (to be) my obligation to take due care of the sick people.

8. Iíll (to have) a two-daysí rest before my next turn to be on duty.

9. Iíll (to meet) with my friends.

10. Weíll (to visit) some museums on Saturday.

11. Theyíll also (to be happy) to see me.

12. Weíll (to enjoy) just seeing each other.

13. I think weíll (to visit) a restaurant next week.

14. My parents (to encourage) me in my desire to become a biologist.

15. This year I (to realize) my cherished dream to become a student of the biology faculty.

16. I (to manage) to successfully pass my exams to the University.

17. I (to become) a student of the most reputable institution of higher education in Belarus.

18. I (to try) to study to the most of my abilities to achieve my lifeís ambitions.

19. I am happy that I (to justify) hopes of my parents.

20. I hope that Iíll never (to regret) my choice.

21. Maybe Iíll (to consider) my future job connected with genetics problems.

22. In the evening, when Iím at home, we (to have) dinner together.

23. We (to use) the possibility to exchange the news.

24. Before going to bed I (to take) a shower and (to clean) my teeth.

25. I often (to sit up) far into the night.

26. What (to be) your bedtime?

 

Ex. 14. Use the verbs in the right tense form.

1. All living things (to consist) of cells.

2. There (to be) many types of cells.

3. Cells (to exhibit) considerable variation in properties.

4. Almost all cells (to have) a nucleus.

5. Ribosomes (to make) proteins as the nucleus (to tell) them.

6. Cilia (to look) like minute hairs.

7. The students (to have) to pay for the education until 1930 but children from the poor families (to have) an opportunity to study for free.

8. Excavations (to reveal) solid remains of animals which earlier (to inhabit) our planet but (to be) now extinct.

9. The fossils (to prove) that the animal kingdom (not to remain) unchanged but (to be) in a process of steady and continuous development.

10. Ages ago primitive people (to hunt) animals for meat.

11. Take an umbrella with you. It (to rain).

12. Listen! Somebody (to sing).

13. Itís a nice day today but yesterday it (to rain) all day.

14. The accident (to happen) last Sunday afternoon.

15. Jenny (to fall) asleep while she (to read).

16. Itís only 9 oíclock and Ann ( to go) to bed already.

17. My mother never (to travel) by air.

18. Jane (to be) a good friend of mine. I (to know) her for a long time.

19. Linda (to read) a newspaper. She (to read) it for two hours.

20. How long you (to live) in this house? Ė About 10 years.

21. The bus (to be) late. We (to wait) for a long time.

22. I (to be) ready now. I (to finish) my work.

23. The weather is nice at the moment. It (not to rain).

24. What (to do) your sister? - Sheís a dentist.

25. You can turn off the radio (I/not/listen) to it.

26. Carol broke her arm. It (to happen) when she (to paint) her room.

27. Yesterday she (to walk) along the road when she (to meet) Jim.

28. They (to stop) to talk for a few minutes when they met.

29. How fast you (to drive) when the police (to stop) you.

30. I (to learn) English for six months.

31. I (to know) Sarah for a long time.

32. How long you (to be) on holiday?

33. How long you (to wait)?

34. Belarus (to be) an independent country since 1991.

35. My aunt (to live) in Australia for many years.

36. What (to do) next weekend? - ďNothing specialĒ

37. Do you know about Dally? Ė She (to leave) her job. She told me last week.

38. We (to have) a party next Sunday. I hope you can come.

39. We (to meet) at Johnís house at 8íoclock tomorrow.

 

Ex. 15. Write questions in the correct tense.

1. You (to work) today?

2. Why you (to look) at me?

3. Where (to live) your parents?

4. What (to mean) this word?

5. It (to rain) a lot in winter?

6. What you usually (to do) at the weekends?

7. How often you (to read) a newspaper?

8. What time your father (to finish) work in the evenings?

9. What organisms (to appear) first on Earth?

10. How long our solar system (to exist)?

11. How the nervous system (to function)?

12. What all living things (to consist) of?

13. You (to speak) English?

14. You (to watch) TV last night?

15. It (to rain) on Sunday?

16. What you (to do) when the phone rang?

17. Diane (to start) her new job yet?

18. You ever (to be) to London?

19. How long you (to be) married!

20. You (to know) her for a long time?

21. It (to rain) all day?

22. How long your brother (to learn) English?

23. Where you (to be) last night?

24. What time you (to finish) your work?

25. You ever (to meet) famous people?

26. The letter (to arrive) yesterday?

27. The letter (to arrive) yet?

28. How many plays and poems Shakespeare (to write)?

29. You (to wear) your new shoes yet?

30. Your parents (to have) a holiday this year? (2 variants)

31. You (to be) here tomorrow?

32. How old he (to be) next Monday?

33. The exam (to be) difficult? (3 variants)

34. You (to phone) me tomorrow?

35. Where we (to go) for our holidays next year?

36. What time we (to meet) tomorrow?

 

Ex.16. Put the verbs in Present and Past Simple Tenses in the Active Voice and translate the sentences.

1. Friends (to play) an important role in a personís life.

2. A friend (to be) a real treasure if you (to have) one. You (to have) one of the most valuable gifts in life.

3. We (to make) friends at school.

4. We (to appreciate) our friendship very much.

5. She (to help) me when I (to be) in trouble.

6. Dasha (to know) me better than I know myself.

7. They (to be) rich who (to have) true friends.

8. She never (to hurt) me.

9. Iím afraid I (to be) not such a good friend for her as she (to be) for me.

10. My friends (to trust) me.

 

UNIT II

 

GRAMMAR. ACTIVE AND PASSIVE VOICE. TOPICS. THE UNIVERSITY. MY FACULTY.   READING. ORGANIC MOLECULES. SPECIES.

 

The Belarusian State University

 

The Belarusian State University is the largest educational, scientific and cultural centre in the republic of Belarus.

Its history began on October, 30 1921 when it was founded due to the efforts of many people; among them there were such famous personalities as M.N. Pokrovsky, V.P. Volgin, E.F. Karsky, K.A. Timiryazev, D.N. Pryanishnikov. The first rector of the University became academician Vladimir Ivanovich Picheta. 1390 students began attending regular classes at its three faculties: workerís, medicine, social sciences.

14 professors and 25 associate professors began their active work almost immediately. From the very beginning the BSU established relations with different foreign countries such as Germany, Lithuania, Poland. The connections with European countries promoted the development of the University which, in fact, created the educational system of the Republic. The BSU gave the beginning of several institutes, which further became independent. They were Minsk Medicine Institute, Minsk Law Institute, Minsk Pedagogical Institute, the Belarusian Institute of National Economy.

The BSU also made great contribution to the development of the Belarusian Academy of Sciences, the State Library and many research institutes.

Today the BSU has 5 prominent research institutes, 4 natianal scientific centres, 20 scientific centres, 172 departmens, 114 scientific labs. More than 18000 students attend 20 faculties: Physics, Radio-Physics, Applied Mathematics, Chemistry, Geography, Biology, Philology, Journalism, History, Philosophy, Law, International Relations.

There have several new faculties and colleges recently appeared. They offer such up-to-date sciences as social technologies, management in the social sphere, marketing, design, international tourism.

Tuition at the University is mostly free of charge and the students receive grants and stipends. Some students pay for their education but study according to the same plans.

The University is staffed by highly qualified teachers. Among them there are academicians, professors, Doctors of science. They teach students, deliver lectures, conduct seminars, supervise laboratory work and practical training of students and post-graduates.

The University provides the students and the teaching staff with the facilities for research work. The Students have their own Science Society and carry out scientific research in different laboratories with up-to-date devices and apparatus.

Itís interesting to notice that the number of foreign students is increasing gradually. This may be the result of the BSU participating in many student exchange programs. In fact, the BSU effectively cooperates with more than 60 universities over the world.

Some words must be said about the restoration made in the university campus. Four wonderful monuments appeared when the BSU was going to celebrate its eightieth anniversary. They are the sculptures to famous Belarusian humanists. The students enjoy spending time there by sitting on the benches and talking about studentís life.

In conclusion we should name some of the outstanding people who graduated from the BSU: K. Krapiva, P. Hlebka, P. Browka, I. Melezh, R. Baradulin, N. Gilevich and many others.

 

Answer the questions.

1. When was the BSU founded?

2. Who was the first rector?

3. Who made great contribution to foundation of the University?

4. There were only 3 faculties first, werenít there?

5. What countries did the University establish relations with?

6. Which institutes did the BSU give the beginning?

7. How many institutes, faculties, chairs, labs does the University have?

8. How many students attend the lessons?

9. What faculties are popular among the students?

10. Do the students of the BSU have to pay for their education?

11. How is tuition at the University conducted?

12. Do the students have their own Science Society?

13. Why is the number of foreign students constantly increasing?

14. Do you like the University?

15. How does it look like?

16. Do you know any outstanding personalities who graduated from the BSU?

 

I. Make sentences using the following words and expressions.

1. the largest, the BSU, educational centre, in the Republic of Belarus, scientific, is, cultural.

2. workers, began attending, 1390 students, three faculties, at its, social sciences, regular classes, medicine.

3. the development of the University, in fact, promoted, which, the connections with European countries, created, of the Republic, the educational system

4. the State Library, the Belarussian Academy of Sciences, many research institutes, and, of, also, the development, made great contribution to, The BSU.

5. is staffed, highly qualified, the university, by, teachers.

 

II. Complete the following sentences.

1. 14 professors and 25 associate professors ...

2. The connections with European countries ...

3. Today the BSU has ...

4. The university is staffed ...

5. They teach students ...

6. Itís interesting to notice ...

7. The students enjoy ...

 

The Biology Faculty

 

The Belarusian State University was founded in 1921 and in 1922 the Pedagogical Faculty began its work. That Pedagogical Faculty included the first biological departments: botany, zoology and human physiology. So the year 1922 can be considered the birth year of the Biology faculty though the independent department of natural history was opened in 1931.

To enter the Pedagogical Faculty students had to pass three oral exams: physics, maths, social science. There were three terms in a year and lessons took place usually in the evening from 5 p.m. till 8 p.m. Some courses were obligatory, some others students were allowed to choose. To move up to the next course students had to pass tests. If anybody didnít pass two or more tests, he remained in the same course for the second year.

An interesting fact is that students had to pay for their education until 1930 but children from pour families had opportunity to study free.

University teachers carried out not only pedagogical but also research work with the students. The first works in the field of Belarusian flora and fauna were made. Moreover, they began researches in new fields such as functional and evolutional morphology of animals; physiological processes in a plant cell; selection and hybridization of plants. That meant that the basis and main principles of Belarusian science were formed exactly at that time.

Our faculty is famous for its zoological museum but only few students know that it was created in 1922. In 1930 the BSU Botany garden was founded.

Very soon the Biology Faculty began to enlarge, some new departments were opened: the department of plant taxonomy, plant physiology and microbiology on the basis of the department of botany. The department of zoology was divided into two: zoology of invertebrates and zoology of vertebrates.

The surprising fact is that since 1927 the teaching had to be conducted in the Belarusian language only. The exception was made for the
Jews who studied in Jewish.

In 1950s the chromosomal inheritance theory was prohibited. Nevertheless the chair of genetics was founded in 1957.

In 1960s-70s investigations in many fields were carried out. Such departments as the department of microbiology, biochemistry and ecology appeared at our faculty.

In 2001 the Biology Faculty got a new building in Kurchatova, 10 with more study-rooms, new labs, new equipment. There were enough space for the zoological museum and the greenhouse there.

Today our faculty includes nine departments: the department of Botany, Zoology, Phisiology and Biochemistry of Plants, Phisiology and Biochemistry of Human and Animals, Genetics and Biotechnology, Biochemistry, Microbiology, Molecular Biology (created in 2002) and the department of Ecology and Teaching Methods of Biology.

The dean of the faculty is V.V.Lysak. Concerning social and cultural life of the students one shouldnít forget about the theatre at the Biology faculty. Its performances are popular among the students and teachers. The faculty has its own billboard newspaper ďVitaĒ. The internet version of it exists too. Itís always a great pleasure to read a new issue, full of humor, smart jokes, interesting facts and useful information.

Our students are always proud of their faculty.

 

 

Answer the questions.

1. Which year can be considered the birth year of the Biology Faculty?

2. What exams did the young people have to pass to enter the faculty?

3. When did the lessons usually take place?

4. Was education free of charge at that time?

5. What researches did teachers and students carry out?

6. When was the zoological museum founded?

7. New departments were opened in 1930s-1940s, werenít they?

8. Teaching was conducted in the Belarusian language, wasnít it?

9. What departments were opened in 1950s-1960s-1970s?

10. When did the Biology Faculty get a new building?

11. How many departments does the faculty include today?

12. What are they?

13. Who is the dean of the faculty?

14. What do you know about the social and cultural life of the students?

15. Are the students proud of their faculty?

 

I. Make up sentences using the following words and expressions.

1. the Pedagocial Faculty, in 1921, The Belarusian State University, and began its work, in 1922, was founded

2. three terms, there were, took place, and lessons, in a year, from 5 p.m., in the evening, usually, till 8 p.m.

3. to pass tests, had, students, to the next course to move up.

4. the basis and the main principles, were formed, of Belarusian science, that meant, exactly at that time, that

5. the chromosomal inheritance theory, in 1950s, was prohibited

 

II. Complete the following sentences.

1. Some courses were obligatory ...

2. An interesting fact is ...

3. Moreover, they began researches in new fields ...

4. Very soon the Biology faculty began to enlarge ...

5. The surprising fact is ...

6. Today the faculty includes ...

7. Concerning social and cultural life ...

8. Itís always a great pleasure ...

 

READING MATERIAL

 

TEXT A

 

I. Read and translate the text.

Organic Molecules

 

The molecules found in living organisms vary tremendously in all ways including complexity. Usually they vary from complex to more complex! A molecule of table sugar, which comes from sugar cane or sugar beets, is composed of 45 atoms: 12 of carbon, 22 of hydrogen, and 11 of oxygen. Its chemical formula is C12 H22 O11. Starch molecules, which are found in all plants, contain thousands of atoms of carbon, hydrogen, and oxygen. Protein molecules are often much larger still.

These large molecules are called organic molecules. All organic compounds contain carbon, in addition to other elements.

Many chemists of the eighteenth and early nineteenth centures felt it was impossible to learn much about organic compounds. They felt that these complex compounds could be made by an animal or plant but not by a chemist in his laboratory. Only after Wohler synthesized urea and Kolbe synthesized acetic acid did these beliefs change.

It was found that urea was made of carbon, hydrogen, oxygen, and nitrogen in the proportions expressed by the formula CON2H4 - a molecule of eight atoms, this is better written as CO(NH2)2. ņs study progressed, it became apparent that a simple formula for a compound is not always sufficient. Just ŗs the position of letters determines the word, so the position of atoms determines the type of molecule.

The formula CO(NH2)2, for urea, does not fully indicate the position of each atom relative to the other atoms. A better way of showing what we know of the makeup of the urea molecule is to use a structural formula.

 

 

II. Mind the pronunciation of the following words:

molecule [′mOlikjHl] carbon [kRbn] hydrogen [′haIdrIGqn] oxygen [′OksIGqn] chemical [kemIkql] protein [proutIn] laboratory [lq′bOrqtqri]  

 

III. Mark the following statements as true or false:

1. Urea was the first chemical compound to be synthesized.

2. The properties of organic molecules fully depend on the number and kinds of atoms they are made up of.

3. Starch molecules are the simplest of all organic molecules.

4. The molecules containing carbon and other elements are called organic.

5. A structural formula of a molecule shows the number of atoms it consists of.

6. Some centuries ago scientists could easily synthesize organic compounds.

 

T E X T B

 

Read and translate the text:

 

Species

 

There are many different groupings beginning with species and ending with kingdom. Thus, you and all other human beings belong to the species Homo sapiens. In addition, you and all other animals belong to the group Kingdom Animalia.

A system for classifying organisms has developed gradually over the past 300 years. It was not until the late seventeenth century that an Englishman, John Ray (1627-1705), developed a clear concept of species. To him a species consisted of offspring of similar parents. The concept has been modified since the time of Ray. We now look upon a species as a group of individuals that can breed with one another. At the same time individuals of one species do not usually breed with individuals of other species in nature. We must emphasize the ďin natureĒ because many species can crossbreed under artificial conditions even though they do not under natural conditions.

It was left to the eighteenth-century Swedish biologist Carolus Linnaeus to establish the rules that are used for naming organisms. Linnaeus gave every species that he knew a name of two words. Hence his system is known as binomial nomenclature. The first word of the species name is the name of the genus to which it belongs. The second name is the so-called descriptive or trivial name. Both words are Latin or Latinized Greek (later systematists have not always used classical words in naming organisms). The genus and descriptive name together constitute the species name of the organism concerned. For example, the large group of cats was given the generic (genus) name Felis. A particular group of cats was given the trivial name Leo. These words together, Felis Leo, are used for the lion, one species of cat. The scientific name of the common house cat is Felis domesticus; of the tiger, Felis tigris. All are cats, but each is a different species of cat.

Linnaeus listed 4,236 species of animals in his Systems Naturae of 1758. The total today is almost a million known species. We are sure there are just as many, and possibly more, that have not been named.

To ensure that no two groups of animals get the same specific name, a very elaborate system has been set up for classifying animals. There is even an international court of biologists that will decide any disputed cases of naming that occasionally occur.

 

GRAMMAR EXECISES

 

Ex. 1. Put the verbs in brackets in the right form. Use Present Simple or Past Simple, Active or Passive.

1. Itís a big factory. 500 people (employ) there.

2. Water (cover) most of the Earthís surface.

3. Most of the Earthís surface (cover) by water.

4. The park gates (lock) at 6.30 p.m. every evening.

5. The letter (post) a week ago and it (arrive) yesterday.

6. Ronís parents (die) when he was very young.

7. I was born in London but I (grow) up in the north of England.

8. While I (be) on holiday my camera (steal) from my hotel room.

9. While I (be) on holiday my camera (disappear) from my hotel room.

10. The company (be) not independent. It (own) by a much larger company.

11. I (see) an accident last night. Somebody (call) an ambulance but nobody (injure) so the ambulance (not/need).

12. Where (these photos/take)? In London? (you/take) them?

13. Belarus (situate) in the centre of Europe.

14. Belarus (border) on Poland, Baltic States and Russia.

15. Minsk (be) the capital of Belarus.

16. Belarus (call) the land of lakes.

17. BSU (Belarusian State University) (open) in 1921.

18. The Academy of Sciences of Belarus (consist) of more than 40 institutions.

19. Visitors (allow) into the house and grounds between 9.00 a.m. and 5.30 p.m.

20. Iím very sorry we couldnít repair your car today, but it (repair) tomorrow. (Future simple).

21. The bank robber didnít get for. He (catch) near London last night.

22. In 1921 Ireland (divide) into Northern Ireland and the Republic of Ireland.

23. The University campus (destroy) almost completely during the war.

24. Lake Naroch (use) for both scientific investigations and academic purposes.

25. The billboard newspaper of the biology faculty (call) ďVitaĒ.

26. Zoological museum of the biology faculty (create) in 1922.

27. Minsk first (mention) in chronicles in 1067.

28. Belarusian flax products well (know) abroad.

29. The Belarusians (accustom) to working hard.

30. Many territories in Belarus are unique places where infinite nature (save) untouched.

31. Every 4 years a president (elect) in the USA.

32. More cars (build) in the Detroit area than anywhere else in the USA.

33. Lunch (serve) in the cafeteria from 11.00 to 2.30.

34. You (ask) not to touch the furniture.

35. Visitors (request) not to feed the animals.

36. The staff (not permit) to accept tips.

 

Ex. 2. Change the following sentences from active to passive voice.

1. The delegates had received the information before the recess.

2. The teacher should buy the supplies for this class.

3. Somebody will call Mr. Watson tonight.

4. Martha was delivering the documents to the department.

5. Somebody calls the president every day.

6. John is calling the other members.

7. The fire has caused considerable damage.

8. The company was developing a new procedure before the bankruptcy hearing began.

9. John will have received the paper by tomorrow.

10. The milkman brings the milk to my door but the postman leaves the letters in the hall.

11. In future perhaps they wonít bring letters to the houses, and we shall have to collect them from the post office.

12. People steal things from supermarkets every day, someone stole 20 bottles of whisky from this one last week.

13. The postman clears this box 3 times a day. He last cleared it at 2.30.

14. Normally men sweep this street every day, but nobody swept it last week.

15. Someone turned on the light in the hall and opened the door.

16. We never saw him in the dining-room.

17. We serve hot meals till 10.30 and guests can order coffee and sandwiches up to 11.30.

18. Passengers leave all sorts of things in buses. The conductors collect them and send them to the Lost Property office.

19. An ambulance took a sick man to hospital.

20. You canít wash this dress, you must dry-clean it.

 

Ex. 3. Rewrite the sentences in the passive, making the underlined words the subject of the sentence.

1. Someone showed the child how to use the telephone.

2. They declared him ďpersona non grataĒ. They allowed him only 48 hours to leave the country.

3. They gave him artificial respiration.

4. Why didnít they offer her the job?

5. Didnít they promise you a rise in salary at the beginning of the year?

6. What did they pay you for doing the job?

7. Someone should tell her never to do that again.

8. They asked you to meet me here at 11 oíclock.

9. Will someone send me the details?

10. We shall send you the goods as soon as they are available.

11. Someone must teach that boy a lesson.

12. Everyone knows this fact very well.

13. They opened the theatre only last month.

14. People will soon forget it.

15. You must write the answers in ink.

16. Someone has taken two of my books.

17. We have already filled the vacancy.

18. What should one do in such case?

19. Did they say anything interesting?

20. You should keep milk in the refrigerator.

21. I donít think anyone can do it.

22. You must finish the work by 7.

23. They are now manufacturing this type of computer in many countries.

24. No one could possibly have known the secret.

25. Has someone made all the necessary arrangements?

26. The police kept the man in custody.

27. Does someone clean all the rooms regularly?

 

Ex. 4. Translate into Russian. Pay attention to the Passive Voice.

1. In many flowering plants the seeds are enclosed within a fruit.

2. When some sea weeds are boiled in fresh water the brown colouring matter is dissolved and the seaweeds become bright green.

3. In sexual reproduction the egg is fertilized by motile spermatozoids.

4. The mossy ďcarpetĒ is formed by many plants living together.

5. During mitosis each chromosome divides into two so that two new sets are formed.

6. Most of fungi are composed of the many cells.

7. A form of ďsexualĒ mating has been rarely observed in bacteria.

8. In the laboratory most bacteria can be induced to grow in culture media.

9. Growth may be neither normal nor healthy without vitamins even when food has been taken in the right proportions.

10. According to differences in their properties and chemical composition, vitamins are classed as A, B, C, D, etc.

11. Young animals suffer from rickets if they are not provided with vitamin D.

12. Rickets is prevented by ultra-violet radiation.

13. Vitamins B and C are widely distributed in fresh fruit and vegetables.

14. Hormones are produced in small quantities, they are carried in the blood-stream.

15. The brain is protected by the skull and the lungs are protected by the ribs.

16. Bones have an ouher layer which is called periosteum.

17. It has been found that each side of our brain is responsible for different skills.

18. The cells that make up the brain are called neurons.

19. The brain is connected to the rest of the body by the spinal cord.

20. The brain is arranged in areas that relate to different parts of the body.

 

Ex. 5. Change the following sentences from active to passive voice.

1. Dogs guard the warehouses.

2. The watchman called the police. The police arrested the man.

3. The court tried the man, found him guilty and sent him to prison.

4. They are repairing my piano at the moment.

5. They invited Jack but they didnít invite Tom.

6. The guests ate all sandwiches and drank all the beer. They left nothing.

7. Passengers shouldnít throw away their tickets as inspectors may check these during the journey.

8. Has someone posted my parcel?

9. Why did no one inform me of the change of the plan?

10. Tom Smith wrote the book and Brown and Co. published it.

11. Iím afraid we have sold all our copies but we have ordered more.

12. You must keep dogs on leads in the gardens.

13. They havenít stamped the letter.

14. They didnít pay me for the work..

15. He escaped when they were moving him from one prison to another.

16. She didnít introduce me to her mother.

17. They threw away the rubbish.

18. A Japanese firm makes these television sets.

19. An earthquake destroyed the town.

20. A machine could do this much more easily.

21. Visitors must leave umbrellas and sticks in the cloakroom.

22. We canít repair your clock.

23. The police shouldnít allow people to park there.

24. They are watching my house.

25. The examiner will read the passage 3 times.

26. Candidates may not use dictionaries.

27. You neednít type this letter.

28. Nobody has used this room for ages.

29. We have warned you.

30. You shouldnít leave these documents on the desk. You should lock them up.

 

Ex. 6. Open the brackets. Put the verbs into active or passive.

1. Today minerals (form) almost half of Australiaís exports.

2. Australia also (export) lots of wood, meat, butter, fruit and wine.

3. Many of these products (export) to the Pacific countries, especially Japan and the West of the USA.

4. Australia (discover) as a market for American products at the end of the 18-th century.

5. The first products from the USA (arrive) in Australia in 1792.

6. In the early 19-th century Sydney (can/reach) faster from the West Coast.

7. Today Australia mainly (import) machines and computer equipment.

8. Students (do) a lot of the work.

9. This room (use) only on special occasions.

10. Bicycles must not (leave) in the hall.

11. These artificial flowers (make) of silk.

12. Far more money (spend) on food now than 10 years ago.

13. The wine should (open) about 3 hours before you (use) it.

14. The paintings (exhibit) till the end of the month.

15. The seals (feed) at the zoo twice a day.

16. Who (write) it?

17. Who (write) it by?

18. A special edition (write) for children.

19. The idea (interest) you?

20. She (show) the easiest way to do it.

 

Ex. 7. Put it the verbs in proper Tense Form.

1. My friend usually (to have) dinner at 4 o'clock. 2. Most of the biology students (to live) in the hostel. 3. Last year we (to study) botany. 4. Some Soviet scientists (to take part) in the International Conference on Genetics next year. 5. Biology faculty (to have) its own library. 6. I (to give) you this book some days later. 7. These young men (to play) football in the last championship. 8. Everybody (to go) to the collective farm in September. 9. First-year students (to finish) school last summer. 10. Our newspaper ďVitaĒ (to be) always very interesting.

Ex. 8. Change the sentences into Passive Voice.

1. British scientists solved this problem many years ago. 2. Enormous numbers of different plants and animals populate the Earth. 3. We can divide these organisms into 2 groups. 4. First-year students know the characteristics of these animals. 5. The Italian investigator Francesco Redi overthrew the theory of spontaneous generation. 6. Redi carried out a simple set of experiments. 7. He covered the tubes with paper, and no maggots and flies appeared in them. 8. Scientists placed Fungi and Bacteria in the plant kingdom. 9. We shall use computers at the exams at every institution of higher education. 10. Soviet Government opened our University in 1921. 11. Young scientists will use complex technique in their work. 12. These authors received very important results and summarized them in a large publication.

 

Ex. 9. Open the brackets and put the verbs in.

1. Jane (to play) the piano in the sitting-room (now; yesterday after supper; in half an hour). 2. The scientists of the British University (to investigate) this phenomenon (last year; at present; for the next 3 months). 3. We (to study) chemistry (for the next two years; last term; this year), 4. This author (to publish) the results of his scientific work (every month; very soon, regularly last year). 5. I (to visit) the library regularly (in future; some years ago; now). 6, My sister Olga (to read) (for the whole next night; constantly; when you came). 7. We (to calculate) the results (later; from time to time; when our scientific supervisor ŮŗÝŚ into the laboratory). 8. Biochemists (to observe) this reaction (from morning till evening yesterday; next week on Friday; day and night). 9. This substance (to dissolve) very quickly (when we added some water to it; if we add some water to it; right now). 10. Newspapers (to discuss) ecology problems (for the last decade; all the time; for many years on). 11. We (to demonstrate) the importance of vitamins by a simple experiment (tomorrow after the clashes; at this moment; yesterday at that time).

 

Ex. 10. Open the backets and choose the necessary form and translate into Russian.

1. Soviet scientists (will be conducting, are conducting, were conducting) researches in different fields of science and engineering even in the hard years of the war. 2. The biologist (is designing, was designing, will be designing) new methods of investigation at present. 3. The students of our group (will be working, are working, were working) in the laboratory all the day tomorrow. 4. New methods of using genetics in practice (are being explained, were being explained) for the whole lesson. 5. She (was being often asked, is being often asked) questions at the seminars this term. 6. A. new apparatus (is being created, was being created) by one of our researchers for five years.

 

Ex. 11. Put the verbs in the correct tense form and translate the sentences into Russian.

1. Their function (wasnít established; has not been established) definitely yet. 2. It (has earlier been discovered; was earlier discovered, had earlier been discovered) that within the boxlike cells of living plants was a little sphere, the nucleus. 3. Much progress (has been made; was made; has made) in disclosing the secrets of photosynthesis lately. 4. He (has observed; had observed; is observing) flies flying over the meat before it became covered with maggots. 5. Let us sŚŚ what (is happening; has happened; happened) to the gametophyte in a heterosporous plant. 6. Question of much the same sort (is asked; has been asked; have been asked) for at least 2,500 years. 7. It (is discovered; has been discovered; had been discovered) that some dyes will selectively stain specific structures in cells. 8. The flasks in which no maggots appeared (were closed; have been closed; had been closed) and the air could not penetrate. 9. Redi (has repeated; had repeated; repeated) a familiar observation: maggots appeared in decaying meat. 10. As we look back and summarize the changes that (have occurred; had occurred; has occurred) in the evolution of green land plants, we can see two distinct trends.

 

UNIT III

 


Date: 2015-02-03; view: 1276


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