written by: DulceCorazon•edited by: Paul Arnold•updated: 12/24/2009
Microbes are microscopic living organisms. They are ubiquitous in nature, meaning they are present everywhere and yet they are too small to be seen by the naked eye. Learn more about the microbe world with the key facts presented below.
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Essential Facts about Microbes
Microbes are divided in different categories which include bacteria, protozoa, viruses, fungi, algae and Archaeans.
DNA is the genetic material found in most bacteria. Viruses have genetic material which can either be DNA or RNA.
There are only about 3% of microbes that can cause disease and these are known as pathogens. Non-pathogens do not cause disease and comprise the majority of the existing microorganisms.
Some non-pathogenic microbes are helpful and some have no effect at all. Microbes that are beneficial and at the same time live in our body are called indigenous microflora or indigenous microbiota.
Indigenous microflora are beneficial by occupying certain spaces or areas in our body. They slow down the growth of pathogens by using up the food supply, and secrete materials such as waste products, toxins, antibiotics.
Diseases that are caused by microbes are categorized as infectious disease and microbial intoxication. Infectious disease is caused by opportunistic pathogens colonizing the body while microbial intoxication is caused by a toxin produced by microbes from outside the body and then ingested by a person. Infectious disease is the world’s number one cause of death.
Microbes are vital to life on our planet. Photosynthetic bacteria such as algae and cyanobacteria produce more oxygen than plants by photosynthesis.
Many microbes are responsible for the decomposition of dead organisms and waste materials and are known as decomposers. They exist in decaying organic substances and return inorganic nutrients to the soil producing a fertilized soil. Some microbes are capable of decomposing industrial waste such as chemicals and oil spills.
Microorganisms also play a major role in the food chain. Since they are relatively small, they are eaten by tiny animals which serve as food to larger animals. They are considered to be the starting point of many food chains.
Microbes are widely used in genetic engineering to create genetically altered plants which can result in greater yields, and crops that taste better and are more resistant to pests. Microbes can also be genetically altered to produce vaccines, insulin, types of growth hormones and other helpful substances.
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Highlights about Microbes
Microbes are the oldest organisms, and have existed on Earth for more than 3 billion years.
Among the estimated 3 billion species of microbes, only about 5% have been discovered.
60% of the overall mass of all living organisms on Earth consists of microorganisms.
Without microbes, existence of all other living organisms is impossible.