Viruses are pathogens that can only reproduce inside host cells. They hijack host cell machinery to produce more viruses, which are then released to infect more cells. Viruses come in many forms, including those that cause common colds and flu, as well as more serious diseases like HIV/AIDS. Vaccines work by exposing the immune system to a weakened or killed form of the virus to develop immunity against future natural infections.

1. Viruses Viruses are insidious pathogens, they attack cells from the inside. They hijack your own DNA and use it against you. A virus cannot be treated with antibiotics, it can only run its course until your immune system kicks it out. ..Even then, the virus may lay dormant within the cells and come back at a later date Adenovirus - cause of the common cold

5. nucleotide

6. Virus Structure

9. 1. Attachment 2. Penetration - the virus is engulfed by the cell (Cell can enter Lysogenic or Lytic Cycle) 3. Biosynthesis - viral components are made (protein coat, capsid, DNA/RNA) 4. Maturation - assembly of viral components 5. Release - viruses leave host cell to infect new cells (often destroys host) Viruses multiply, or replicate using their own genetic material and the host cell's machinery to create more viruses. Viruses cannot reproduce on their own, and must infect a host cell in order to create more viruses.

11. Lytic vs Lysogenic Pathways of viruses Starring the phage named Lambda See: http://highered.mcgraw-hill.com/sites/007352543x/student_view0/chapter20/lambda_phage_replication_cycle.html

14. Developing a vaccine for AIDS is difficult because it is a RETROVIRUS. RNA mutates easily and each individual virus can be slightly different from the others. In fact, different viruses can exist within the same person. See: HIV coloring

19. Some parents are opting out of immunizations due to fears about vaccine safety. In response, government agencies are producing commercials to encourage parents to get their child vaccinated. Discuss: 1. What are the risks of vaccines? Are they safe? 2. Would you have your own child vaccinated? 3. Should the government force immunizations?