DNA Discovery Webquest Name: A webquest is an educational tool that requires students to use the Internet to find information effectively. Since this is our first webquest, I have provided viable websites for the information you need. You might need to copy and paste the website into your browser. You might not need all of the sites that are provided. This webquest should take you no more than one hour. This will help you learn how to effectively sift through information for what you need. In order to receive an A on this project, you must: Complete every portion of the webquest in complete sentences. Complete the open-ended portions of the webquest in your own words. Good luck! 1. Frederick Griffith http://www.absoluteastronomy.com/topics/Frederick_Griffith Frederick Griffith’s famous experiment was conducted in 1928. In his experiment, the dead/alive S strain bacteria plus dead/alive R strain bacteria killed mice. His experiment led to the discovery of the process of ____________________________________. Griffith’s Famous Experiment: Transformation – see page 191 in your biology book for a better picture. 1 2. Oswald Avery http://library.thinkquest.org/20465/avery.html In 1944, what did he discover that DNA is responsible for? 3. Alfred Hershey and Martha Chase http://en.wikibooks.org/wiki/Structural_Biochemistry/Nucleic_Acid/DNA/Hershey -Chase_Experiment http://www.accessexcellence.org/RC/AB/BC/Experiments_that_Inspire.html In 1952, their experiments showed that _____________________________ is the genetic material instead of _____________________________. See page 192 in your book for another picture of this. 2 4. Erwin Chargaff http://www.dnai.org/timeline/index.html - Click on Chargraff and read about it. Watch “Chargaff’s Ratios.” Chargaff used relative proportions of bases in DNA to come up with his rules for base pairing. What are four sources of DNA that he used? http://fig.cox.miami.edu/~cmallery/150/gene/chargaff.htm Adenine (A) pairs with __________________________ Guanine (G) pairs with ________________________ The bases that are purines include ________________________ & _________________________. The bases that are pyrimidines include _______________________ & _________________________. 5. Rosalind Franklin. http://www.wisegeek.com/what-is-x-ray-crystallography.htm What is X-ray crystallography (a.k.a. X-ray diffraction)? http://www.dnai.org/timeline/index.html What did she discover about the shape of DNA? 3 6. James Watson and Francis Crick. http://www.dnai.org/timeline/index.html - Click on Watson and Crick a. What did they receive the Nobel Prize for in 1962? b. What is the difference between Pauling’s structure and the actual structure of DNA? c. Please draw an accurate diagram of Watson and Crick’s DNA model below. Include proper base-pairing, the sugar-phosphate backbone, and the double-helix structure. You may make more than one drawing if you find it necessary. Extra Credit: http://nobelprize.org/educational_games/medicine/dna_double_helix/ Play the game and record what three organisms you had: 1. 2. 3. 4 .