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What Are the Major Function of Bacteria?

Bacteria are all around, inhabiting every environment on the planet in numbers so high it is difficult to begin to comprehend, from the doorknob in your room to the inside of your mouth. Although they have a bad name because they can cause death and illness, bacteria are often beneficial and, without them, life could not exist on this planet. With so many bacteria in your life, you might wonder about their purpose. Like most forms of life, the simple answer is that the major function of bacteria is to reproduce itself, but the full answer is much more complicated and interesting.

Function and Form
- Bacteria come in a bewildering variety of shapes. Some look like coils or zig zags, and others look like little balls. Bacteria that have tails, stalks or other forms of propulsion are found in liquid environments, and can sometimes use their stalks to absorb nutrients. From their shape scientists know that these bacteria function in liquid. Bacteria with multiple fibers cling to surfaces, performing their functions while attached to objects.
Bacteria That Benefit
- A majority of bacteria are beneficial to life. Their functions are so diverse that one bacteria may be beneficial to an organism and be deadly to another. Bacteria can clean pond water, are essential to creating honey and yogurt, and maintain balance and aid in digestion in the human gut. The functions of these types of bacteria are not specifically to help humans, but rather to help themselves find food and successfully reproduce. Because humans provide bacteria with homes and sources of food, they have evolved to survive in and on humans without harming them.
Bacteria That Harm
- Some bacteria nourish and reproduce themselves by harming their hosts or even killing and then eating the organisms. Bacteria like E. Coli 0157:H7 are often in the news because of the danger they pose to humans. This type of E. Coli lives in the stomach of cattle and is harmless to the cattle, but can be deadly to humans. Other bacteria, like salmonella and giardia, are harmful to humans but don̵7;t usually kill; rather, they make the human host ill.
Decomposers
- At their most basic, most bacteria are decomposers. Regardless of whether they are harmful or beneficial, bacteria feed themselves by decomposing matter. Bacteria in the soil break down organic matter, while bacteria in the gut break down nutrients. When bacteria attack and kill an organism, they decompose the organism by eating it. Dinosaur bodies don̵7;t exist today because they were decomposed by bacteria.

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