Bacteria: plural of bacteria. Micro-organisms that lack chlorophyll, but it is sometimes included among the lower floors and consist of cytoplasm within a membrane, as well as a capsule and lack of differentiated nucleus. Its nuclear material scattered is located by the cytoplasm and consists of a single chromosome, which consists of a strand of DNA. Bacteria, have a spherical outer variable ( coconuts, swab ( 41 bacilli; or spiral ( 41 spirits; They reproduce by simple division. The capsule has cilia and flagella that bacteria can be transferred by the liquid medium. The majority does not tolerate the temperature higher than 100 ° C. They have a great importance in the natural cycles of ecosystems. They act rotting organic matter by breaking it down into nutrients for plants. Some species are pathogenic for man, while many others are very useful in industry and genetic engineering.