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Bacteria are very, very tiny. So tiny, that millions of them can fit on the tip of your finger! Because they are so small, you can't see the billions of them in the air, on your skin, and even inside your body! Bacteria may be small, but many of them are quite tough and can live just about anywhere.
Bacteria often get a bad reputation because some of them cause disease. But many others are completely harmless. Some bacteria even do good things for us, such as turn milk into cheese! Bacteria were among the first life forms on Earth.
Despite their small size, bacteria are the most abundant of any organism on Earth. And they're everywhere! Bacteria can be found in the air, soil, water, on you, and inside you. In fact, there are more bacterial cells inside your gut and on your skin than there are cells in your entire body - no matter how many times you try to wash them off!
The cells of all bacteria (and therefore, the cells of all Monerans) are classified as "prokaryotic", the simplest and most ancient of the cell types. Prokaryotes lack many of the structures found in the more complex, eukaryotic cells.
Bacteria often get a bad reputation because certain types are responsible for causing a variety of illnesses, including many types of food poisoning. However, most bacteria are completely harmless and many even perform beneficial functions, such as turning milk into yogurt or cheese and helping scientists produce drugs to fight disease. Bacteria were among the first life forms on Earth.
The bacteria are the most numerous of any of the living organisms. Bacteria have evolved an amazing diversity of means of acquiring the resources they need to live and reproduce. This remarkable diversity has enabled the bacteria to inhabit virtually every known environment on Earth, from the hot sulfur springs of Yellowstone to the glacial ice of the Arctic to the depths of the ocean floor.
The mere word "bacteria" typically conjures up images of germs and uncleanliness. The great deal of media attention paid to illnesses caused by bacteria such as E. coli and Salmonella, have helped earn the bacteria their notorious reputation as disease-causers. Though many diseases can be attributed to bacteria, other species are completely harmless and several perform beneficial functions, including converting milk into cheese and yogurt, and aiding in the production of pharmaceuticals to treat disease. Bacteria were among the first life forms on Earth.
Last modified December 17, 1998 by the Windows Team
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