Microorganisms
Microorganisms are tiny living things such as bacteria, viruses and fungi, some helpful and some harmful.
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Microorganisms are tiny living things such as bacteria, viruses and fungi, some helpful and some harmful.
- Bacteria reproduce by binary fission
- Yeast is a single-celled fungus
- Many microbes help recycle nutrients
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Microorganisms?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Microorganisms. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Microorganisms in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Microorganisms helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Microorganisms in detail
Microorganisms are living things too small to see without a microscope, including bacteria, viruses, fungi and protists. Many are useful, such as decomposers, yeast in baking and bacteria that make yoghurt, while a small proportion cause disease.
Bacteria are single-celled and reproduce by binary fission, fungi such as yeast and moulds feed on organic matter, and viruses are not cells and need a host to reproduce. Aseptic technique, using sterile equipment, prevents contamination when culturing microorganisms. They are essential in nutrient cycles and in industry.
How the interactive helps you understand Microorganisms
Watch the cell model in the interactive. Use any sliders or buttons it offers to change the values and see how the cell model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Microorganisms.
Real-life uses and examples
- Connect Microorganisms to health, food and medicine in everyday life.
- Use Microorganisms to interpret a diagram, graph or microscope image from a practical.
- Structure a longer answer about Microorganisms by moving from definition to example to consequence.
Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Microorganisms
What is Microorganisms?
Microorganisms are tiny living things such as bacteria, viruses and fungi, some helpful and some harmful.
What are the most important points about Microorganisms?
The main points are: Bacteria reproduce by binary fission; Yeast is a single-celled fungus; Many microbes help recycle nutrients.
Why is Microorganisms useful?
Understanding Microorganisms helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Microorganisms?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Microorganisms?
Related topics in Biology include Teeth and Dental Health, Exercise and Fitness, Characteristics of Living Things.