Middle School Science/Biology/Bacteria

Concept
Bacteria are most widely distributed organisms. These are unicellular micro-organisms. A scientist named Leeuwenhoek discovered bacteria in 1677 for the first time. Later, Louis Pasteur and Robert Koch worked on them. This was a milestone in the history of biology and medicine. They discovered that bacteria produce many harmful diseases in man and animals. Bacteria(Singular is bacterium) range from 1um to 10um in length and from 0.2um to to 1 um in width. Bacteria can be observed under light microscope. The habitat of bateria is not specific. They are found everywhere, in air, water, living as well as dead bodies of organisms and even in glaciers and hot springs

Kinds Of Bacteria
On the basis of various shapes and forms, bacteria are divided into four types. First is Cocci(Singular Coccus) and means rounded. The second is Bacilli(Singular Bacillus) which is rod-like. The third one is Spirilla(Singular Spirillium) and means spiral shaped and the last is Vibrios( Singular Vibrion) which means comma shaped.