Viruses

Structure: Protein Coat around DNA strand

Living: No; are not cells, they have no way of producing food on their own, just parasites who live off of other hosts and reproduce within them.

               Bacteriophage Virus                          Poliomyelitis Virus

  (plentiful in killing sewage, killing bacteria)            (attacks nuerones)

Life Cycle of Bacteriophage

             Step One:                     Step Two:                  Step Three:

        (Virus injects DNA)             (Assemble More)   (Escape Dead Cell to Attack More)

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