double arrow

Microorganisms

Microorganisms are very tiny one-celled organisms, viruses, and bacteria. They are found everywhere in the world. They are found in all living things, plants and animal. Microorganisms can live in the air, on land, and in fresh or salt water environments. Some of them can be harmful and causes diseases, but there are some microorganisms that are needed for living things to survive.

All existing microorganisms can be divided into two main groups – aerobic and anaerobic. Aerobic organisms must have atmospheric free oxygen for their life and growth. But free oxygen is not favourable for the development of anaerobic microorganisms.

Any minute virulent microorganisms may invade the human body. But due to the local protective agents of the human organism they are destroyed. In this case no disease occurs.

However the local protective agents of the human body are not always able to destroy completely the invading microorganisms. In this case a local or general infection may occur.

Most of the microorganisms produce diseases when they enter the tissue and destroy it. But the human organism can fight against microorganisms which have passed its first protective barriers, such as skin and mucous membrane.

Answer the questions

  1. What are microorganisms?
  2. Where are they found?
  3. Where can microorganisms live?
  4. What groups can all microorganisms be divided into?
  5. What organisms must have free oxygen for their life and growth?
  6. When do most of the microorganisms produce diseases?
  7. In what case does no disease occur?
  8. In what case may a local or general infection occur?

Speak English.

  1. Микроорганизмы – это крошечные одноклеточные организмы.
  2. Некоторые микроорганизмы могут быть вредными.
  3. Некоторые микроорганизмы необходимы живым существам для выживания.
  4. Мельчайшие вирулентные микроорганизмы могут проникнуть в тело человека.
  5. Они проникают в ткань органа и уничтожают её.
  6. Но организм может бороться с вредными микроорганизмами.
  7. Если защитные средства организма уничтожают проникающие микроорганизмы, то болезнь не наступает.
  8. Местная или общая инфекция может произойти тогда, когда защитные средства тела не могут уничтожить опасные микроорганизмы.

TOPIC 41. VIRUSES

You already know that viruses cause many infectious diseases that ruin the health of people. Studying this topic you’ll learn about the structure, origin and spread of these small infectious agents.


Понравилась статья? Добавь ее в закладку (CTRL+D) и не забудь поделиться с друзьями:  



Сейчас читают про: