- •Unit I
- •About myself
- •Vocabulary
- •Vocabulary Notes
- •My Working Day
- •Vocabulary
- •Vocabulary Notes
- •My Day Off and My Hobbies
- •Vocabulary
- •Vocabulary Notes
- •Reading material text a
- •The Cell
- •If we examine a thin piece of a plant under a microscope we shall see
- •Cells: the Smallest Units of Life, their Structure
- •Crammar exercises
- •Unit II
- •The Belarusian State University
- •Vocabulary
- •I. Make sentences using the following words and expressions.
- •II. Complete the following sentences.
- •The Biology Faculty
- •Vocabulary
- •I. Make up sentences using the following words and expressions.
- •Vocabulary Notes
- •II. Mind the pronunciation of the following words:
- •III. Mark the following statements as true or false:
- •Species
- •Grammar execises
- •Unit III
- •Belarus
- •Vocabulary
- •Vocabulary Notes
- •Self check
- •Minsk-the Capital of the Republic of Belarus
- •Vocabulary
- •Vocabulary Notes
- •Self check
- •Reproduction and Growth
- •Bacteria: their Construction
- •Crammar exercises practice modals
- •Practice substitute words
- •Unit IV
- •The United Kingdom
- •Vocabulary
- •Vocabulary Notes
- •I. Make sentences
- •II. Complete the sentences using the text.
- •Vocabulary
- •Vocabulary Notes
- •Self check
- •My Future Profession
- •Botanist
- •Ecologist
- •Biochemist
- •Vocabulary
- •Reading material
- •Algae: the Simplest Green Plants
- •Crammar exercises practice participle
- •Practice infinitive
- •Practice gerund
- •Unit V
- •Questions:
- •II. Rewrite and translate in writing paragraphs 2, 4.
- •III. Put questions to the underlined words.
- •IV. Put the verbs in brackets in the right form and voice. Translate the sentences into Russian in writing.
- •V. Translate the following sentences into Russian in writing, pay attention to different forms of adjectives.
- •Questions:
- •II. Rewrite and translate in writing paragraphs 2, 4, 5.
- •III. Put questions to the underlined words.
- •IV. Put the verbs in brackets in the right form and voice. Translate the sentences into Russian in writing.
- •V. Translate the following sentences into Russian in writing, pay attention to different forms of adjectives.
- •VI. Rewrite and translate the following sentences into Russian. Pay attention to the modal verbs.
- •VII. Rewrite and translate the following sentences into Russian, pay attention to different meanings of the words.
- •Questions:
- •II. Rewrite and translate in writing paragraphs 2, 4.
- •III. Put questions to the underlined words.
- •IV. Put the verbs in brackets in the right form and voice. Translate the sentences into Russian in writing.
- •V. Translate the following sentences into Russian in writing pay attention to different forms of adjectives.
- •VI. Rewrite and translate the following sentences into Russian. Pay attention to the meanings of the verbs.
- •VII. Rewrite and translate the following sentences into Russian, pay attention to different meanings of the words.
- •VIII. Put in some, any, something, anything, nothing, nobody and translate the sentences into Russian.
- •Questions:
- •II. Rewrite and translate in writing paragraphs 2, 4, 6.
- •III. Put questions to the underlined words.
- •IV. Put the verbs in brackets in the right form and voice. Translate the sentences into Russian in writing.
- •V. Translate the following sentences into Russian in writing, pay attention to different forms of adjectives.
- •Questions:
- •VII. Rewrite and translate the following sentences into Russian, pay attention to different meanings of the words.
- •Questions:
- •Исключения
- •Pronouns and Substitute words
- •(Местоимение и словазаменители)
- •The word One
- •Слово One
- •Слово-заместитель that (those)
- •Слово-заместитель this (these)
- •II. Articles
- •III. Numbers (Числительное)
- •IV. Pronouns (местоимения)
- •V. Оборот there is (there are)
- •IV. Безличное it
- •VII. Adjectives (прилагательное)
- •VIII. Adverbs (наречия)
- •IX. Tenses Active Voice
- •Passive Voice
- •X. Modal Verbs (модальные глаголы)
- •Основные значения модальных глаголов
- •XI. Participle
- •Функции причастия
- •I. Определениe (Attribute (какой?, какая?)
- •Models:
- •2. Participle II
- •II. Обстоятельство (Adverbial Modifier (как?, почему?, когда?)
- •1. Participle I (Active and Passive)
- •2. Participle II
- •3. Perfect Participle
- •Причастные обороты
- •1. Сложное дополнение (Complex Object)
- •2. Сложное подлежащее (Complex Subject)
- •3. Независимый причастный оборот (Absolute Participial Construction)
- •XII. Gerund
- •Функции герундия
- •1. Подлежащее (Subject)
- •Часть составного именного сказуемого (Part of a Compound Nominal Predicate)
- •Часть составного глагольного сказуемого (Part of a Compound Verbal Predicate)
- •4. Прямое дополнение (Direct Object)
- •5. Косвенное дополнение (Indirect Object)
- •6. Определение (Attribute) Герундий в данной функции употребляется после следующих абстрактных существительных с предлогами:
- •7. Обстоятельство (Adverbial Modifier)
- •Герундиальные обороты (gerundial constructions)
- •Употребление инфинитива без частицы to
- •Функции инфинитива
- •1. Подлежащее (Subject)
- •2. Часть сказуемого (Part of the Predicate)
- •3. Дополнение (Object)
- •4. Определение (Attribute)
- •5. Обстоятельство (Adverbial Modifier of):
- •Инфинитивные обороты (infinitive constructions)
- •1. Сложное Дополнение (Complex Object)
- •2. Сложное подлежащее (Complex Subject)
- •3. Инфинитивный оборот
- •(The For-To-Infinitive Construction)
Reproduction and Growth
Reproduction of bacteria is usually by fission: an individual cell enlarges and splits into two, each of the resulting pair being an exact replica of the parent cell (in the absence of mutation). Filamentous species reproduce by the elongation and branching of their filaments. A few bacteria multiply by a budding process. Methods of reproduction are almost invariably asexual, though a form of ‘sexual’ mating has been rarely observed.
In the laboratory most bacteria can be induced to ‘grow’ (reproduce) in liquid or on solid culture media. Nutrient requirements, atmospheric conditions correct pH value (acidity or alkalinity) of the medium, osmotic pressures and temperatures are rendered optimum for the multiplication of species in vitro. Some bacteria will grow in a simple defined medium consisting of a few salts in aqueous solution (trace elements are provided by the impurities found in all chemicals, even those described as ‘pure’). Others, including many pathogenic species, require protein degradation products, such as digested meat, in the constitution of media suitable for their growth. Some fastidious pathogens need media enriched with blood or other highly nutritious substances.
Say whether the following statements are true or false:
Methods of reproduction of bacteria are mainly asexual.
Bacteria never multiply by budding.
Bacteria usually reproduce by dividing into numerous parts.
Bacteria can’t be grown in the laboratory.
Numerous requirements have to be met in order to make bacteria reproduce in vitro.
The medium enriched with nutritious substances is required for some pathogenic bacteria.
T E X T B
Bacteria: their Construction
Bacteria are very small single-celled organisms (microorganisms) 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 of thousands in a single drop of milk.
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 cholerae (cholera). The type of bacterium which forms a coil or spiral is Spirillum.
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.
Bacteria usually reproduce by simply splitting in two. When temperature conditions are favourable, about 37°C for most bacteria, they can divide about оncе every 30 minutes. In theory, one bacterium could form about 140 000 000 000 000 bacteria at the end of 24 hours. In fact, this does not happen because the supply of food soon runs out, poisonous wastes accumulate, and after a time no more bacteria can survive. Although most bacteria reproduce by dividing in two, some bacteria can reproduce sexually, during which the contents of one bacterium flow into another.
Bacteria are very tough. Different kinds can live in almost every environment, from hot springs to arctic frost. Many can form a type of spore under certain conditions. A spore is capsule inside which a bacterium can survive for years of drying out, intense heat or disinfectant. Few of disease bacteria can make spores.