Cards (16)

  • viruses are non living.
  • viruses are classified based on their nucleic acid type
  • types of viruses
    • DNA
    • RNA
    • RNA Retrovirus
  • examples of RNA Retrovirus
    • HIV
  • examples of RNA viruses
    • tobacco mosaic
    • ebola
  • examples of DNA viruses

    -lambda phage
  • Lambda Phage
    • complex structure
    • DNA nucleic acid
    • host cells are bacteria and e-coli
  • Tobacco mosaic virus
    • helix shape
    • have +ssRNA which can be directly translated to proteins
    • host cells are tobacco plants
  • HIV virus

    • icosahedral shape
    • have single strand RNA
    • reverse transcriptase used to produced cDNA
    • host cells are white blood cells
  • Ebola virus

    • envelope helix shape
    • have -ssRNA which needs to be transcribed to mRNA before being translated
    • host cells are humans
  • lytic cycle

    • virulent virus DNA injected into host cell cytoplasm
    • viral protein made
    • genetic info/DNA replicated
    • virions assemble
    • cells LYSE
  • lysogen pathway

    • non virulent virus injected into host cell cytoplasm
    • as a provirus
    • virus produces repressor proteins (stops transcription)
    • latent virus enters lytic cycle (when host cycle is weak)
  • How do antivirals work?
    inhibit replication by...
    • forgetting viral enzyme so cant replicate DNA
    • forgetting viral antigen to prevent entry to host
  • What is the focus of disease control?
    SPREAD OF INFECTION
  • summary of ebola outbreak
    • poor hygiene caused virus to spread
    • 4900 deaths
    • no vaccine so focus was on reducing spread
  • methods of control of virus
    • quarantine
    • sterilisation of equipment
    • rapid testing of people