1. The Virus

2. What is a Virus? Virus Latin for Poison Non-cellular particle with DNA or RNA 1 or 2 Protein Coats (Capsids) May have Viral Envelope - Phospholipids DO NOT respire or grow ONLY function in a living cell

3. Questions/Discussion Do Viruses Respire? What type of genetic material do viruses have? Can they have both DNA and RNA?

4. How are they Classified? Shape of their protein coat (capsid) Important in infection Type of nucleic acid they contain DNA or RNA NEVER Both

5. Reproduction Cycles

6. How do Viruses Replicate? The lytic cycle: 1- absorption/attachment 2- injection/entry 3- replication of viral parts 4- assembly 5- release by lysis Results in death of host cell Virulent virus (only lytic cycle)

7. Lets Go Through the Steps of the Lytic Cycle Together!!!

8. Lysogenic Cycle First steps just like lytic!! Does NOT destroy the host cell Nucleic acid joins the cell’s DNA. Viral DNA becomes a part of hosts cell DNA (prophage) Could go on for years Temperate virus (capable of using the lytic and lysogenic cycles) i.e. HIV, cold sores, shingles

9. Lysogenic Cycle

10. Lets Go Through the Steps of the Lysogenic Cycle!!!

11. Both Cycles Together

12. Types of Viruses Animal viruses: Rabies, Polio, Mumps, Chicken pox, Small pox, and Influenza. Plant Viruses: Tobacco mosaic virus (TMV), Banana streak virus, Carrot thin leaf virus Bacterial Virus: Bacteriophages ( T1, T2, T3, and T4.) SPECIFIC in what type of cell and what type of organism they infect Polio – human nerve cell T4 – only certain strains of E. coli

14. Different Types of Viruses ADENOVIRUS Respiratory infections; colds

15. Polio

16. Influenza Virus Virus that causes the flu

17. How the Flu virus infects you? http://www.youtube.com/watch?v=Rpj0e mEGShQ http://www.youtube.com/watch?v=Rpj0e mEGShQ

18. Small Pox

19. TMV

20. Retroviruses RNA viruses that contain reverse transcriptase This enzyme allows RNA to produce DNA HIV is an example of the virus

22. How HIV works? http://www.youtube.com/watch?v=mzfnx CEsck4 http://www.youtube.com/watch?v=mzfnx CEsck4

23. How Vaccines Work http://www.youtube.com/watch?v=kwVfc c1S7IU http://www.youtube.com/watch?v=kwVfc c1S7IU

24. Questions/Discussion What some differences between the lytic and lysogenic cycle? What type of virus is HIV? How is HIV one of the most successful viruses in reproducing?

25. Viruses: Living or Not?