History The discovery of virus

Adolf Meyer (Germany) in 1883 to investigate diseases that bring tobacco leaves mottled yellow. He concluded that the cause is the organism that is smaller than bacteria. In 1893, DIMITRI IVANOWSKI (Russia) doing the same investigation by filtering the extract of diseased tobacco plants using bacterial filter. He hypothesized that if the cause of the disease is bacterial, then the organism can not pass through the filter bacteria. However, once the results of the filter is injected into a healthy tree, the tree turns mosaic disease. However, ivanowsky still conclude that the organism causing the disease is a bacterial pathogen that is smaller than the size of ordinary bacteria and produce racun.Pada 1987, MW Beijerinck conduct further investigations on tobacco leaves. He concluded that the disease-causing organisms are smaller than bacteria and can only breed in the living body.
WENDELL STANLEY (the United States) in 1935 has managed to crystallize the pathogenic organism of leaf temabakau. Organism is then given the name of TMV (tobacco mosaic virus). He also showed that the viral protein and nucleic acids.

And here are the characteristics of a virus :

The size of an average-sized body 0,02-0,03μm greatest dn size 200nm
Body structure consisting of nucleic acid (DNA or RNA) surrounded by a protein coat called a capsid
Diverse body shapes, such as polygons, elongated (filament), bentu T, and the shape of the stem (silendris)
Can be inside or outside the cell. If located outside the cell, the virus shaped just like an ordinary chemical compounds.

Can only thrive in living cells
Usually stable at pH 5.0 to 9.0
Virus activity can be removed by ultra violet rays and Xray, but the substance of antibiotics and other antiseptic agents have no effect against
Can act as an agent of the disease, meaning that the virus can infect cells and cause changes, dysfunction, or cell death.
The virus is also a genetic agent, meaning it can cause genetic changes in cells infected.