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Microbiological techniques- gel electrophoresis

Scientists in labs use a technique called gel electrophoresis which allows them to separate a mix of DNA fragments by size . This is used in conjunction with PCR (polymerase chain reaction) and restriction d...
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Answered by Lizzie B. Biology tutor
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What is a virus?

A virus is made of DNA wrapped in a coat made of protein. It is very small, typically nanometres across (one billionth of a metre). Viruses are different from bacteria as they are smaller and are not structu...
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Answered by Lizzie B. Science tutor
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What is a mole and why is it useful?

Molecules are very small, much smaller than we can see with our eyes. For this reason, we can’t simply just count the number of molecules in a sample by looking at it. Even if we could, there are so many mol...
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Answered by William M. Chemistry tutor
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How should you structure an A-level English Literature essay?

One way in which you could structure an essay would be with a diamond structure. This is when your answer begins with your point (your argument- clearly established at the beginning of the essay) progresses ...
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18082 Views

How do I write a good introduction and conclusion?

A conclusion should not be a repetition of your introduction. In your introduction you should analyse the key words of the question and establish the points you will discuss in depth in your essay. You shoul...
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