Viruses

1. Viruses Noa, Kennedy, Neal

2. Introduction • Viruses are not classified in any of the six kingdoms because they are not living • Need a host to survive • Do not have cells present • Do not eat and produce waste • Only can reproduce • Needs help of a cell to reproduce

3. Vocabulary • Capsid- A protein shell that surrounds a virion (single viral particles made up of genetic material). • Epidemic- A rapid outbreak of an infection that affects many people. • Bacteriophages- Viruses that prey on bacteria. • Pathogen- infectious agent • Vaccine- A substance used to stimulate the production of antibodies and provide immunity against one or several diseases

4. Influenza A VirusCells and Structure • Not made of cells, therefore it is not Eukaryotic or Prokaryotic nor unicellular or multicellular. • Composed of a lipid membrane that comes from the host’s plasma membrane, and spike- like proteins known as HA (Hemagglutinin) and NA (Neuraminidase). • HA and NA are the proteins that determine the subtype of the Influenza Virus. • The structure is also composed of the RNA polymerase and other less significant proteins.

5. Energy, Environment, and Movement • Gets its energy by attaching itself to a host. • It inserts a virus particle into the cell to make the cell change the function to benefit the virus. • It is a parasitism symbiotic relationship, because only the Virus benefits. • When the body recognizes the virus, it begins to make antibodies to keep the virus from infecting other healthy cells. • Moves from one organism to another through natural factors, such a coughing or sneezing.

6. Life Cycle • When Influenza enters the body, the first thing it does is attach itself to an acid molecule in the respiratory system. • The virus is then engulfed by a cell, which later release the viral molecules to the cytoplasm so they can travel to the nucleus. • The RNA is replicated, and new genes and proteins move to the cell membrane wrapped in a protein layer. • Lastly, the new viral molecules bud through the cell membrane to find new cells to invade. • The cell then dies a couple of hours later.

7. Reproduction FactsAnd Evolution • Influenza A does not reproduce asexually or sexually, because it reproduces by attaching to a host. • This virus evolves extremely rapidly to avoid vaccinations. • Because most strands of Influenza change so rapidly, a new vaccine is made every year to fight off the harmful virus. • Most of the time, vaccines do not recognize the strands from the season before, because the strands are constantly changing. • Influenza is the 6th leading cause of death in American adults. • In severe cases, Influenza can effect almost all parts of the body. • It often becomes an epidemic.

8. Rabies Virus • Known as the rabies virus • Not uni- nor multicellular • Not a prokaryote nor a eukaryote • Does not have a cell wall

9. Structure • The rabies genome encodes 5 proteins • This determines the structure of the virus • Contains no cells • Only has RNA • Bullet shaped

10. Energy • Does not need energy • Does not need food • Neither autotrophic nor heterotrophic • Takes control of host to reproduce • Uses energy of host to reproduce

11. Environment • Cannot move by itself • Only gets along with warm-blooded hosts • Travels with their host • Parasitism relationship with host • Can only reproduce when with their host • Attack the nervous system of host

12. Reproduction • Can only reproduce when with host • Cannot produce sexually or asexually • Can last weeks or months • If not treated can be fatal

13. Evolution • Can survive without any cells or DNA of its own • Does not produce waste • Needs host to reproduce • Good at hiding in nervous system of host

14. Interesting Facts • The rabies virus is over a thousand time smaller than bacteria • Raccoons are the most common animal with rabies • Without a host a virus is just a package of chemicals

15. Zaire Ebolavirus • Commonly called the Ebola Virus • Has a fatality rate of up to 90% • Outbreaks happen in remote parts of Africa • Fruit bats are a common host • There is no vaccine

16. Cells and Structure • Not made of cells • Capsid is a part of the virus • Has RNA

17. Energy and Reproduction • Attaches onto host cells, so when the cell is replicated the cell reproduces the virus • Not heterotrophic or autotrophic • Takes energy from host cells to use on its own

18. Stimulus and Evolution • Since this is a virus, Ebola will change and adapt rapidly • Parasitic relationship with host.

19. ConclusionCells and Structure • Viruses are not living, even though they have many characteristics that living organisms have. • Not eukaryotic or prokaryotic • No cell wall • Mainly composed of nucleic acid (DNA or RNA),a lipid membrane, proteins, and a capsid. • Spike-like proteins are used to attach to other cell surfaces. • Structure allows the virus to attack hosts

20. Energy and Environment • Viruses do not directly need energy. • Take over a host to reproduce, and infect other healthy cells. • Can not do anything until they taken over a cell. • Neither heterotrophic or autotrophic • Viruses do not react to the environment, unless if they are inside a cell, because that’s when they “come alive”. • Once the body recognizes the virus, it produces antibodies to kill the virus. • Viruses have a parasitic relationship to their host, because the virus benefits by reproducing, while the host is being “taken over”. • Viruses move from body to body by tiny infected droplets that usually come from sneezing or coughing.

21. Reproduction and Evolution • Viruses do not reproduce asexually or sexually. • As said before, viruses can only reproduce once they have taken over another cell. • Once a virus is inside a host, it can take over all of the healthy cells around it, unless if the body recognizes the virus. • Vaccines help the body become more resistant to a virus, so that if the body does catch a virus, it is able to produce a much stronger immune response. • Because viruses have a lot of mutations, produce many offspring, and have a short life cycle, they are able to evolve and change very rapidly.

22. Facts about Viruses • There are a million virus particles per milliliter of seawater  • The genetic information of Viruses could be double or single stranded and either DNA or RNA. • Thousands of viral mutations arise by chance everyday. • Scientists have been debating since 1892 on whether or not viruses are living. • Scientists also think that a large DNA based virus lived in a bacterial cell more than a billion years ago to form the first cell nucleus.

23. Sources • Ebola virus disease. (n.d.). . Retrieved April 16, 2014, from http://www.who.int/mediacentre/factsheets/fs103/en/ • What is Ebola Virus?. (n.d.). . Retrieved April 16, 2014, from http://www.primehealthchannel.com/ebola-virus-symptoms-pictures-structure-facts-and-history.html • Viruses. (n.d.). . Retrieved April 15, 2014, from http://www.biology-online.org/biology-forum/about8808.html • Facts About Viruses That Will Shock You. (n.d.). Facts About Viruses That Will Shock You. Retrieved , from http://preventdisease.com/news/09/121409_two_facts_about_viruses_will_surprise_you.shtml • Viruses and Evolution. (n.d.). History of Vaccines RSS. Retrieved , from http://www.historyofvaccines.org/content/articles/viruses-and-evolution

24. Sources Continued • Cool Facts About Viruses. (n.d.). . Retrieved , from http://www.virology.ws/2009/10/19/ten-cool-facts-about-viruses/ • May 2014. (n.d.). Discover Magazine. Retrieved , from http://discovermagazine.com/2010/apr/20-things-you-didnt-know-about-viruses • The Rabies Virus. (2011, April 22). Centers for Disease Control and Prevention. Retrieved , from http://www.cdc.gov/rabies/transmission/virus.html • Types of Influenza Viruses. (2014, January 15). Centers for Disease Control and Prevention. Retrieved , from http://www.cdc.gov/flu/about/viruses/types.htm • Influenza. (n.d.). University of Maryland Medical Center. Retrieved , from http://umm.edu/health/medical/altmed/condition/influenza