Bacteria
Bacteria are very small organisms. Some bacteria can cause disease.
bacteria cell structure
bacteria cell structure

Bacteria consist of only a single cell—but don't let their small size and seeming simplicity fool you. They are an amazingly complex and fascinating group of organisms. Bacteria have been found that can live at temperatures above the boiling point and in those that would freeze your blood. They "eat" everything from sugar and starch to sunlight, sulfur and iron. There is even a species of bacteria that can withstand blasts of radiation 1,000 times greater than those that would kill a human being. Acteria fall into a category of life called the Prokaryotes. The prokaryotes' genetic material, or DNA, is not enclosed in a cellular compartment
[[http://www.youtube.com/watch?v=gEwzDydciWc (- about bacteria|Video about Bacteria]]

Influenza virus
Influenza virus
A virus is a sub-microscopic infectious agent that is unable to grow or reproduce outside ahost cell. Viruses infect all types of cellular life.Viruses consist of two or three parts: all viruses have genes made from either DNA or RNA, long molecules that carry genetic information; all have a protein coat that protects these genes; and some have an envelope of fat that surrounds them when they are outside a cell. Viruses spread in many ways; plant viruses are often transmitted from plant to plant by insects that feed on sap, such as aphids, while animal viruses can be carried by blood-sucking insects.

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