Microbiology is defined simply as the study of microorganisms, with “micro” meaning small and “biology” referring to the study of living things. The microorganisms studied vary widely, and the field of microbiology is broken down into many subfields of study.
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Types of Microorganisms
Microbes are found nearly anywhere on Earth. They are found in boiling pools of water in Yellowstone and in volcanic vents at the lowest depths of the sea. They can live in salt flats and some thrive in saltwater (so much forusing salt as a preservative). Some need oxygen to grow and others do not.
The world’s “toughest” microorganism is a bacteria calledDeinococcus radiodurans, a bacteria that can withstand radiation to a phenomenal degree, as its name implies, but can also survive without water, exposure to strong acids, and even when placed in a vacuum.
Classification of Microorganisms in Microbiology
There are many different ways in which scientists have classified, and in doing so tried to make sense of, the millions of microbes in our midst.
Multicellular vs. Unicellular vs. Acellular
Eukaryotes vs. Prokaryotes
Another way in which microorganisms are classified has to do with the type of cell. These include eukaryotes and prokaryotes:
The Major Classes of Microorganisms
The different types of microbes can also be broken down into:
History of Microbiology
What we now know about microorganisms, which will be discussed further, is relatively new in history. Let’s take a brief look at the history of microbiology:
First microscope/first microorganisms visualized:The first major step in microbiology came about when Antonie van Leeuwenhoek (1632-1723) created the first single lens microscope. Through a lens that had a magnification of roughly 300X, he was able to visualize bacteria for the first time (from scrapings off of his teeth).
Germ theory:The two people most credited with the acceptance of the germ theory were Louis Pasteur and Robert Koch:
Since that time, a few landmarks include the following:
Infectious Microorganisms
When we think of microorganisms, most of us think of disease, though these little “bugs” are overall more likely to help us than hurt us. (Read further to learn about “good microbes.")
Until less than a century ago, and currently in many places of the world, infections with microorganisms were the leading cause of death. The life expectancy in the United States improved dramatically over the last century not only because we are living longer, but mostly because fewer children die in childhood.
The advent of vaccinations and antibiotics, plus even more importantly clean water, has lowered our concern over infectious organisms, but it would be amiss to be arrogant. At the current time, we are facing not only emerging infectious diseases but alsoantibiotic resistance.
Microorganisms That Are Helpful to Humans
Though we seldom talk about it, microorganisms are not only helpful but necessary in nearly every aspect of our lives. Microbes are important in:
Not only do microbes perform many functionsforus—they are part of us. It’s thought that the bacteria in and on our bodies number our cells equally one to one.
You’ve probably heard the latest in healthy eating. In addition to eating broccoli and blueberries, some healthcare providers recommend eatingfermented foodsdaily, or at least as often as possible.Without bacteria, there would be no fermentation.
If you’ve read thenewslately, it’s even been postulated that the bacteria in our guts are responsible for our day-to-day moods. The study of the microbiome is now being used to explain many things, such as why antibiotics may lead to weight gain.
Fields of Microbiology
The Future of Microbiology
The field of microbiology is fascinating, and there is more we don’t know. What we have learned most in the field is that there is so much more to learn.
Not only can microbes cause disease, but they can also be used to develop drugs to fight other microbes (for example, penicillin). Some viruses appear to cause cancer, while others are being evaluated as a way to fight cancer.
One of the most important reasons for people to learn about microbiology is to have respect for these “creatures” that far outnumber us. It’s thought that antibiotic resistance is increased due to improper use not only of antibiotics but of antibacterial soaps.And that is only when looking at the microbes we currently recognize. With infectious diseases emerging, and with our ability to travel almost anywhere in the world on three flights, there is a great need for microbiologists to be educated and prepared.
17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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