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Тема 4. 3. Вирусы. The Future Simple Tense.
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Тема 4. 3. ВИРУСЫ. . THE FUTURE SIMPLE TENSE.
Viruses
Virus is a non - cellular infection agent that can be reproduced only inside living cells. Virus infect all types of organisms, from plants and animals to bacteria and archaea. Virus capable of replicating only in the presence of other viruses (satellite viruses) have also been detected.
Since the publication in 1892 of an article by Dmitry Ivanovsky describing the non - bacterial pathogen of tobacco plants and the discovery in 1898 by Martin Beyerink of the tobacco mosaic virus, more than 6 thousand types of viruses have been described in detail, although it is believed that there are more than one hundred million of them. Viruses are found in almost every ecosystem on Earth, they is the science of virology, a section of microbiology.
In animals, viral infection cause an immune response, which most often leads to the destruction if the pathogenic virus. The immune response can also be triggered vaccines that give active acquired immunity against a specific viral infection.
However, some viruses, including human immunodeficiency virus and causative agents of viral hepatitis, manage to elude the immune response, causing a chronic disease. Antibiotics do not act on viruses, however several antiviral drugs have been developed.
Задание 4. Найдите в тексте английские эквиваленты следующих слов и словосочетаний: Вирус, не клеточная, воспроизводиться, бактерия, способен, присутствие, описывая, открытие, в подробностях, экосистема Земли, наука, раздел микробиологии, возбудители.
Задание 5. Выпишите предложения в которых используются следующие слова и словосочетания: satellite viruses, non – bacterial, tobacco plants, tobacco mosaic virus, microbiology, immune response, leads, acquired immunity, including, human immunodeficiency, hepatitis, chronic disease.
Задание 6. Ответьте на вопросы:
1) What is a virus?
2) What does infect the virus?
3) When did Dmitry I. describe the non - bacterial pathogen of tobacco plants?
4) How much have been types of viruses described in detail?
5) Where are found the viruses?
6) What is the cause of the immune response?
7) Do antibiotics act on viruses?
Тема 4. 5. ИММУННАЯ СИСТЕМА. THE FUTURE CONTINUOUS TENSE.
Immunity.
Immunity means resistance to disease. It is provided by certain white blood cells, which release antibodies and antitoxins into the blood plasma. Many causative factors can stimulate white cells to produce antibodies antitoxins; for example, microorganisms; bacterial, plant and animals toxins; foreign bodies; transplants; transfusion of incompatible blood cells. All such factors are called antigens.
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When infection occurs, inflammation results, and part of this defensive reaction involves antibodies and antitoxins. They are present in the blood and help overcome the microorganisms concerned. Some of these antibodies and antitoxins can remain in the blood for life and prevent any repetition of the same infection. Such life-long protection is called acquired immunity; but unfortunately it does not occur for every type of microorganism.
However, where immunity is possible it can be reproduced artificially in people who have never been infected by a particular microorganism. It may be done by giving a non-immune person a dose of dead microorganisms. This is called vaccination. Dead microorganisms cannot produce disease but they do stimulate the host’s body to produce antibodies and antitoxins against the particular microorganisms concerned. Thus any subsequent infection with these organisms is immediately overcome by the antibodies and antitoxins already present. If there has been no vaccination or prior exposure to disease, acquired immunity is not present. However, all individuals inherit some degree of natural immunity and this helps explain why some people are more resistant to disease than others.
Задание 1. Найдите в тексте английские эквиваленты этих слов и словосочетаний:
1. невосприимчивость к заболеванию 2. вырабатывать анти-
тела 3. все факторы 4. они присутствуют в крови 5. предупреждать повторное инфицирование 6. приобретенный иммунитет 7. искусственно 8. вакцинация 9. они действительно стимулируют 10. таким образом 11. наследовать 12. врожденный иммунитет 13. это помогает объяснить
Задание 2. Выпишите предложения в которых используются следующие слова и словосочетания:
to be provided, causative factors, antigens, to involve, to help
overcome, to remain for life, to occur, to be reproduced artificially a
non-immune person, dead microorganisms, a subsequent infection,
prior exposure, more resistant to disease
Задание 3. Ответьте на вопросы:
1. What is immunity?
2. What is it provided by?
3. What factors can stimulate white cells to produce antibodies
and antitoxins?
4. What happens when infection occurs?
5. How long can antibodies and antitoxins remain in the blood?
6. Does acquired immunity occur for every type of microorganism?
7. Can it be reproduced artificially?
8. How may it be done?
9. What do dead microorganisms stimulate?
10. Is acquired immunity always present?
11. What is natural immunity?
Эталоны ответов:
Задание 1. 1. Harmless, 2. more or less dangerous, 3. according to their shape, 4. associated, 5. less virulent, 6. acute, 7. spores, 8. extremes of temperature, 9. more favourable conditions, 10. destruction.
Задание 2. Обеспечивать дом, принимать участие в, подразделяться на, находиться, растут сплетенными цепями, посвящать, причина заражения, растет в маленький пучок, выдержать, быть высоко устойчивым.
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