Although there are many reasons to study microbiology, the three most important reasons are listed below:
1. Microorganisms are very closely related to a human environment. It is practically impossible to find a sterile surface anywhere around humans. Microbes are present everywhere, even on the skin and inside the bodies of human beings. Therefore, they are important to human health, as many of them cause diseases.
2. Microorganisms are present in every environment on earth. They are integral parts of the food webs of all environments. For example, in fresh water bodies, autotrophic microbes synthesize organic molecules from CO2 and sunlight and serve as food for other organisms, like small fish. These small fish are eaten by bigger fish that serve as food for humans.
Also, microbes are involved in many important environmental nutrient cycles, like the carbon cycle, the nitrogen cycle, and many other elemental cycles. Hence, they maintain a balance in nature.
3. Microbes are important tools of genetic engineering. By genetically modifying microbes, man has succeeded in producing large quantities of biological substances such as hormones, vitamins, enzymes, and growth factors. They are also vital model organisms in biological research.