Lytic lifecycle of a virus

8,040 views

Published on

IB Biology Option F SL

Published in: Technology, Health & Medicine
0 Comments
4 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
8,040
On SlideShare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
70
Comments
0
Likes
4
Embeds 0
No embeds

No notes for slide

Lytic lifecycle of a virus

  1. 1. LyticLifecycle of a Virus<br />AHL Biology<br />Option F<br />
  2. 2. Let´sREVIRUS!!! (revise thevirus)<br />Howmanyquestions can yougetrightonthisquiz?<br />
  3. 3. 11<br />
  4. 4. Viral genomes<br />DNA<br />viruses<br />RNA<br />viruses<br />RNA  DNA<br />viruses<br />ss RNA<br />(Retroviruses)<br /> ds DNA<br />(hepadnaviruses)<br />ds DNA<br />ss RNA<br />ss RNA<br />ss DNA<br /><ul><li>genome is template for mRNA
  5. 5. genome is template for DNA synthesis ("retrovirus")
  6. 6. Requires reverse transcriptase to change RNA into DNA</li></li></ul><li>It will undergo the lytic cycle<br />Bacteriophage<br />Prophage can exist in a dormant state for a long time<br />Virulent phages only undergo a lytic cycle<br />Temperate phages can follow both cycles<br />
  7. 7. Lyticphages – add notes to your diagram as we go through the next few slides<br />Clockwise: Pseudomonas aeruginosa phage; Aeromonas<br />phage; Shigella K II phage; Listeria phage<br />
  8. 8. Life Cycle of a Lytic Phage<br />Step 1 Adsorption: virus attaches to the cell wall surface<br />Step 2 Penetration: entry of the viral DNA<br />Phage T4 adsorption to the cell wall of E. coli<br />
  9. 9. Life Cycle of a Lytic Phage<br />Step 3 Synthesis of early viral proteins<br />Step 4 Replication of viral DNA<br />Phage T2 attacks E. coli<br />
  10. 10. Life Cycle of a Lytic Phage<br />Step 5 Synthesis of late viral proteins<br />Step 6 Assembly<br />Step 7 Lysis and release of mature viruses<br />Lysis of E. coli cell by Phage T4<br />
  11. 11. Life Cycle of a Lytic Phage<br />
  12. 12. Antibiotics and their mode of action<br />
  13. 13. MRSA<br /><ul><li>Methicillin-resistantStaphylococcusaureus
  14. 14. Resistanceto beta-lamantibioticswhichincludethepenicillins and cephelasporins
  15. 15. MRSA is especially troublesome in hospitals where patients with open wounds, invasive devices and weakened immune systems are at greater risk of infection than the general public.</li></li></ul><li>Superbuggonerogue…<br />
  16. 16. Questionstoconsider….<br />What is the situation with regard to MRSA? <br />-Is it emerging? <br />-Highly prevalent? <br />-Why do you think the issue has gained so much press right recently?<br />Do you think that the message that recent articles about MRSA disease highly publicisedin the news were talking about risks associated with sick, hospitalized patients and not the public at large came through?<br />Do you think that the media has portrayed a reliable representation of the threat of MRSA?<br />

×