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Lesson Bacteria: What and How? - Study


Read the information below carefully several times and try to remember the key points.

Click on a chapter to view the information.

Tip: read the information out loud (but in such a way that you do not disturb others).

1. Very Small

Bacteria are very, very small organisms (living things) measuring 0.00001 cm (1 ten-thousandth of a centimeter). They consist of only one cell and you can only see them with a microscope.

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2. Diseases

Bacteria can cause all kinds of diseases. Also contagious diseases such as tuberculosis, diphtheria, the plague and cholera.

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3. Protect

You can protect yourself against bacteria by washing thoroughly (especially your hands) with soap and disinfectant gel, sunlight, vaccinations and medicines that kill the bacteria (disinfect).

Fortunately, most bacteria are good bacteria. We even need them to stay healthy.

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4. Multiplication

Bacteria multiply very quickly. For example, by hot air on stagnant water.

From a single bacterium, 70 million new bacteria can develop within one day.

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5. 30 second rule

If you wash your hands gently and thoroughly for 30 seconds with soap and warm water, you can get rid of many disease-causing bacteria from your hands.

Until recently it was the 20 second rule. But 20 seconds turns out to be insufficiently effective in practice.

Sing a song in your head that lasts 30 seconds. That helps to do it long enough.

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Key points

Key points to remember are:

  • Bacteria are invisibly small
  • Bacteria are organisms
  • Bacteria can make you sick
  • Bacteria grow very quickly
  • Bacteria don't like soap

Next step

Once you have gone through the above information a few times, start doing the exercises that go with it.