PETRI DISH 1QUESTION: What are bacteria?
Bacteria are tiny living beings made up of a single cell. As micro-organisms, individual bacteria are too small to see with the naked eye. They exist in almost all environments on the planet, from volcanoes to the ocean floor, and inside the bodies of almost every living animal on earth.
PETRI DISH 2QUESTION: Are all bacteria bad?
There are many disease-causing (pathogenic) bacteria, but most bacteria are not harmful.
Many of the bacteria found in the human body are helpful. They strengthen our immune systems by fighting off other invading bacteria, help us to digest food, and help to regulate hormone levels.
PETRI DISH 3QUESTION: What is the difference between bacteria and viruses?
Bacteria are living organisms which can multiply to make new bacteria on their own.
Unlike bacteria, viruses are not living organisms; they need to be inside other cells to survive. They invade our body’s cells and tell them to reproduce the virus, helping it multiply.
When viruses or bacteria invade our body, both can sometimes make us feel unwell. It is often hard to tell if it is a bacterium or a virus that is making us sick.
PETRI DISH 4QUESTION: What are antibiotics?
Antibiotics are substances that kill bacteria or stop them multiplying. They do not affect viruses.
They are some of the most important drugs known to medicine. However, in some countries, the majority of antibiotics are not given to humans but to farm animals.
PETRI DISH 5QUESTION: What is antibiotic resistance?
Antibiotic resistance is the ability that some bacteria have to resist being harmed by previously effective drugs. This drug resistance develops amongst bacteria through several mechanisms, including natural selection from one generation to the next. Antibiotic resistance make infections more difficult or even impossible to treat.
A common misconception is that a person’s body becomes resistant to specific drugs. However, it is bacteria and other microbes, not people, which become resistant to the drugs.
PETRI DISH 6QUESTION: Wasn’t penicillin all Alexander Fleming’s work?
Penicillin is commonly associated with Sir Alexander Fleming. In 1928 he noticed a mould, surrounded by a sterile ring, growing on a culture plate of staphylococcus bacteria. Fleming understood that the mould was producing a substance which acted against the bacteria. However he was never able to isolate or purify the substance, which he called penicillin, nor effectively test it on animals or humans.
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