MICROBES – THE FACTORY OF EVERYTHING
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Do you study microbiology in your school?
According to what you have studied, are microbes useful, useless or harmful?
What are microbes?
Microbes, or microorganisms, are tiny creatures that individually are too small to be seen by the naked eye. They are the oldest form of life1 on Earth and, by weight, represent 60% of the biomass of all life on Earth. They live everywhere: in the soil, water, and air, in animal intestines, and in extreme settings such as rocks, glaciers, hot springs, and deep seas. The wide variety of microbial habitats reflects an enormous diversity of biochemical and metabolic traits.
Disadvantages of microbes
Microorganisms can be both very harmful and very useful: some of them are pathogens as they can cause serious diseases, such as malaria, poliomyelitis, diphtheria, and typhoid fever. Some may contaminate food and cause food spoilage or even food poisoning.
Advantages of microbes
However, the majority of microbes contribute to the quality of human life. They make about half the oxygen we breathe. They are the foundation of the food chain that feeds all life on earth. They have been used for thousands of years to make fermented foods such as bread, cheese, and yoghurt. Some soil microbes release nitrogen1 that plants need for growth and emit gases that maintain the precarious composition of the Earth's atmosphere. They are also at work in agriculture, industry, pollution control, and medicine. In our bodies, different microbes help to digest food, ward off invasive organisms and engage in battles with the human immune system.
Microbes are a source of new genes and organisms of value in biotechnology and energy production. Microbial genomes are relatively easy to study, so understanding their genomes helps understand how more complex genomes developed.
Groups of microbes
There are five basic groups of microbes: bacteria, fungi (yeasts and moulds), protozoa, microalgae, and viruses.
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1 Microbes were the first forms of life on our planet and have survived by adapting to ever-changing environments, from simple one-celled life forms to intelligent, decision-making, life-sustaining species in
charge of many primar functions in biochemical and biological balances.
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1 Do you know what nitrogen is? If you need more information about it and its usefulness, surf the Net and find out.
