Bacteria

Bacteria are probably the most common form of life on earth. They are also among the simplest and smallest living things. They are micro-organism, which mean they can seen only under a microscope.
Some bacteria cause disease, but most do not. There are at least 2,000 species of bacteria. Most of them are harmless or helpful to other forms of life, including people.
What is bacteria live?
Bacteria are everywhere. Some live in the mouths, and intestines of animals and of people. Other live on fallen leaves or animal waster; in water, milk, and most food;and on dust and soil. Some bacteria can use hydrogen gas, ammonia, and iron compounds as their food. A few bacteria feed on gases and acids that are poisonous to us.
Most bacteria are killed by heat, yet there are a few kinds that live in hot springs, Freezing does not usually kill bacteria, but it checks their growth. Some kinds of bacteria, but resist drying, strong chemicals, or extreme temperatures by changing into tough-walled spores. The cabteria may last a very long time in this resting form. Under favorable condition, the spores walls burst, and the bacteria become active again.
New and future uses of bacteria
Scientist are finding many ways of making bacteria work for the benefit of people. For example, they have developed a method for producing methane gas by processing the manure (solid wastes) of cattle. Methane is valuable fuel. Like natural gas, it is used for heating homes and factories, and for other energy needs. In the same process, protein and minerals are extracted to be used for cattle feed. Protein rich cattle feed has also been obtained by growing bacteria on wood petroleum, abd sewage wastes.
Some bacteria are used as living insecticides against certaian insect pests.
Scientists are experimenting to find answers to questions such as these; May bacteria useful in fighting other bacteria able to make cellulose, which can be used to make paper? Can bacteria that eat holes in underground deposits of limestone be used to make oil flow more easily? Can bacteria be used to generate electricity? While feeding on certain subtance, some bacteria produce energi that can be converted to electricity. Scientists are traying to devise batteries that can use bacterial energy.