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Biology LibreTexts

19.3: Viruses

  • Page ID
    5940
    • 19.3A: Viruses
      Viruses are obligate intracellular parasites. Probably there are no cells in nature that escape infection by one or more kinds of viruses. Viruses that infect bacteria are called bacteriophages. Outside the cell, they consist of particles called virions.
    • 19.3B: Influenza
    • 19.3C: φX174
      φX174 (phiX174) is a virus that infects the bacterium E. coli. Hence φX174 is a bacteriophage.
    • 19.3D: Smallpox
      Smallpox certainly qualified as one of the greatest scourges of humanity. It regularly killed 25% and sometimes as many as 50% of its victims. Introduced into Europe around the sixth century A.D., smallpox rivaled plague in its ability to decimate entire populations. Introduced into the New World in the sixteenth century, smallpox devastated the native populations and played a far greater role than weaponry in the Spanish Conquest.
    • 19.3E: Retroviruses
      The genome of retroviruses consists of RNA not DNA. HIV-1 and HIV-2, the agents that cause AIDS, are retroviruses.