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Name: Gladys
Status: Student
Age: 14
Location: N/A
Country: N/A
Date: N/A 

Can bacteria kill dangerous germs?

Your question is not clear: 'dangerous germs' ARE bacteria. So your question is: can some bacteria (harmless ones) kill other bacteria that cause disease (pathogenic bacteria). In theory, yes. Some bacteria produce substances that are toxic to other bacteria. However this is never applied to protect food, for instance. It is also not used as medication.

One way of preventing 'dangerous germs' in our food is to let harmless bacteria get there first. That is why yoghurt is longer lasting than fresh milk: the bacteria that are already present in the yoghurt (and that produce the taste) prevent other bacteria to grow. But the yoghurt bacteria don't kill the others. They just compete with food, and since we put lots in there, they overrule the odd 'bad one'.

Trudy Wassenaar

What is needed to answer this question is a definition of the word "germs." The common definition of "germs" are small things people cannot see that make them sick. Translating this to scientific terminology, you are referring to both bacteria and viruses.

So there are two points to make in addressing the question, "Can bacteria kill germs?"

First, since bacteria is a type of germ, and there are lots and lots of types of bacteria, the general answer would be bacteria don't kill themselves.

Second, involves addressing the role of viruses. Viruses tend to use cells to make thousands and thousands of copies of themselves. They use both bacterial cells and cells in your body to do this. A virus will invade a healthy cell, and manipulate it's DNA (or cell programming) to make more copies of the virus. So, the answer to this part of the questions is "no" as well.

Bear in mind, that germs are a natural part of our world. They are everywhere, in the air we breath, on our skin, and in our mouths. Most of the time there aren't enough of them to make us sick, and our immune systems can control them.

Saundra Sample

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