BIO230 Viruses

  1. Viruses

    Characteristics of viruses?
    • Smallest known infectious agent
    • Measured in nanometers (10-9), 1000x smaller than bacteria
    • Also known as nucleoproteins
    • Have hollow protein head containing DNA or RNA.
    • Head is also called a capsid or nucleocapsid.
    • All living organisms have both DNA and RNA, virus only have either DNA or RNA
    • Too small to be seen with regular light microscope.
    • Will not grow on agar plates or broth tubes.
  2. Viruses

    Living organism characteristics of viruses?
    • Are reproduced at a very rapid rate, 1-50k in 1-2hrs (done by host cell)
    • Have genetic DNA or RNA
    • Can change or mutate (done by host cell)
  3. Viruses

    Non-living characteristics of viruses?
    • Have no cell structure
    • Have no cytoplasm (hollow)
    • Have few, if any, enzymes.
    • Carry out no chemical reactions.
    • Obligate intracellular parasite.
  4. Types of Species specific viruses?
    • Animal viruses - infect animal cells
    • Plant viruses - infect plant cells
    • Bacterial viruses (phage) - infect bacterial cells
    • Fungal viruses (phage) - infect fungal cells
    • Protozoal viruses (phage) - infect protozoal cells
  5. Types of Tissue specific viruses?
    • Dermatotropic viruses - skin
    • Pneumatotropic viruses - lungs
    • Hepatropic viruses - liver
    • Neurotropic viruses - neurons
    • Lymphotropic viruses - infects lymphocytes (HIV)
  6. 3 types of virus shapes?
    • Icosahedral
    • Helical or cylindrical
    • Complex shaped virus "The Bug"
  7. 2 catagory types of medications used to treat viruses?
    • Attacks viral DNA or blocks its replication.
    • Blocks formation of viral proteins.
  8. Examples of medications used to treat viruses?
    • AZT, ddI, ddC, Retrovin, Amantadine, Idoxuridine, Methisazone
    • 1. Used against HIV, influenza, severe herpes, smallpox, chickpox

    Protease inhibitors; Norvir, Inverase, Saquinovir, Acyclovir
  9. 2 main immune system responses to viruses?
    • Neutralizing antibodies.
    • Interferons
  10. Viruses; Immune Response

    Mechanism of Neutralizing antibodies?
    • Proteins made by the immune system against specific viruses
    • Antibodies attach to the protein receptors on the capsid of the virus and prevent viral attachment to a host cell.
    • Antibodies are specific.
    • Antibodies are kept in the body forever.
  11. Viruses; Immune Response

    Mechanism of Interferons?
    • Antiviral proteins made by virus infected cells in the body.
    • Interferons pass into surrounding cells and prevent viral take over and replication in the adjacent cells.
    • Interferons are non-specific.
    • Interferons are short-term.
Card Set
BIO230 Viruses
CCBC BIO230 Dr. Jeffrey test 1 material. Covers viruses.