Virus

Virus

1. obligate, intracellular parasites

   • they can exist outside host cell and doing nothing. but they reproduce inside host cell
   • can't produce ATP on their own
   • not cellular

2. origin

   • may need some reading abt the hypothesis
   • – escaped-genes hypothesis
   • – degradation hypothesis
   • – RNA world-origin hypothesis

3. why do we care

   • increase diversity of life
   • genetic info research
   • infects all form of cellular life
     • each human cell can be infected by at least one type of virus
       • how to prevent viral infection
         • get vaccinated
         • antiviral drug
           • interfere virus genome replication

4. epidemic

   • Ebola

5. pandemic

   • AIDS

6. Morphology

   • nonenveloped
   • enveloped

7. genetic material

   • single/double stranded linear/circular 
   • DNA
   • RNA
     • Could be double or single stranded.  most RNA(not just abt virus) are single 
     • +ve sense
     • -ve sense
     • ambisense
   • how do virus copy their genome
     • RNA replicates function as RNA dependent RNA polymerase
     • reverse transcriptase
       • use RNA as a template to produce DNA

8. viral replication

   • lytic cycle
     • produce virons and kill host cell
   • lysosome
     • no virions produced have dormant stage in host cell
   • 6 common phases
     • 1.attach to a host cell and enter into cytosol
       • 2. transcription of viral genome and production of viral protein
         • – host cell machinery used for translation – some viruses have proteases to cut their own proteins
         • 3. replication
           • – host cell supplies nucleotides – RNA genomes have RNA replicases – retroviruses have reverse-transcriptases
           • 4. assembly of new generation of virions
             • – genome packaged into capsid 
             • 5. exist from the infected cells
               • 6. transmission to a new host
               • budding (enveloped virus)
               • bursting (naked virus)
       • plant virus:
         • insect biting the plant; the cell wall disrupted, virus come in
       • animal / bacteria virus
         • attach to a specific molecule on cell wall / plasma membrane

Imágenes y archivos del mapa