1 / 11

Discovering DNA as Genetic Material

Learn about historical discoveries regarding DNA as the genetic material in biology. Topics include Avery's and Hershey-Chase's experiments.

menzies
Download Presentation

Discovering DNA as Genetic Material

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Review Chapter 8 Test Notes – Chapter 9 When you fall, pick something up." Oswald Avery To learn about the historical discoveries surrounding the genetic material, DNA. Title: Biology 3/8/07 Class Topics Objectives: Thursday, January 2, 20208:55 PM

  2. Class Assignments What By When • W.S. 9.1 3/8/07 • Chapter 9 Quiz 1 3/12/07 • Due this class period • Due next class period • Due in the future

  3. Grade Sheet 2A – p. 157 (5 pts.)

  4. Avery’s conclusion • Carbohydrase didn’t block transformation • Proteases didn’t block Transformation • Ribonuclease didn’t block transformation • Deoxyribonuclease blocked transformation • What’s the conclusion? • DNA is the genetic material of bacteria

  5. Avery’s experiment • Problem • Hypothesis • Procedure • Conclusion

  6. From: http://ribonode.ucsc.edu/HuGen/01_80H/01_80Hlec6.html

  7. Hershey-Chase Experiment • 1952 - Alfred Hershey and Martha Chase worked with viruses to support the conclusion that DNA is the genetic material • The specific viruses were bacteriophages (phages) • infects bacteria • Contain both DNA and Protein

  8. Radioactive Isotopes • Isotope - same element (number of protons) but different numbers of neutrons • Unstable or radioactive (releases energy) • Used to follow the different elements throughout the experiment • Phosphorus-32 - DNA not protein • Sulfur-35 - protein not DNA

  9. Graphic taken from the MIT Hypertext

  10. From: http://osulibrary.orst.edu/specialcollections/coll/pauling/dna/pictures/hersheychase-experiment.html

  11. Chapter 9 Quiz 1 Review • Describe 1 of the 3 experiments • Griffith, Avery, or Hershey/Chase • Problem • Hypothesis • Procedure • control & experimental groups, independent & dependent variables • Data • Conclusion

More Related