1. DNA SBI3U

2. WHAT MACROMOLECULE CARRIES GENETIC INFORMATION? Agenda for October 22 nd 2013 1.Intro DNA notes 2.Create DNA

3. TIMELINE OF IDENTIFYING GENETIC MATERIAL 1.Genetic Material Transforms Bacteria - Frederick Griffith, 1931 2.DNA is the hereditary material - Oswald Avery, Colin MacLeod, and Maclyn McCarty, 1944 3.The Genetic Material is DNA - Alfred D. Hershey and Martha Chase, 1952 4.Erwin Chargaff, 1940’s and early 50's 5.M.H.F. Wilkins and Rosalind Franklin, early 50’s 6.James Watson and Francis H.C. Crick, 1953

4. DISCOVERY OF DNA Griffith 2 strains of bacteria  Smooth (pneumonia)  Rough (no pneumonia) Conclusion  Disease was passed  One strain was transformed into the other

5. DISCOVERY OF DNA Avery Isolated macromolecules from killed S cells  DNA, protein, lipids Found that living R cells exposed to S strain DNA turned into S cells Conclusion  DNA released  R strain incorporated this DNA into its cells

6. DISCOVERY OF DNA Hershey and Chase Bacteriophages – virus that attacks bacteria Labeled DNA and protein  Radioactive isotopes  DNA – labeled phosphorous  Proteins – labeled sulfur Conclusion  Viruses must inject DNA into living cell  DNA provided info needed to produce new viruses

8. DNA - DEOXYRIBOSE NUCLEIC ACID Store and transmit genetic information Composed of smaller nucleotides DNA is an ideal genetic material  store information  able to replicate  undergo changes (mutate)

9. STRUCTURE OF DNA Nucleotides – 3 parts Deoxyribose sugar Phosphate group Nitrogenous base  A, T, C, G

10. NITROGENOUS BASES 4 Bases  Adenine (A), Thymine (T), Cytosine (C), Guanine (G) Purine – Double ring  A and G Pyrimidine – single ring  T and C

11. CHARGAFF’S RULE Found amount of guanine equals amount of cytosine  Amount of adenine nearly equals thyamine Chargaff’s rule:C=GA=T

12. DISCOVERING STRUCTURE OF DNA X – Ray Diffraction Maurice Wilkins and Rosalind Franklin Photo 51 Indicated DNA was a double helix http://www.pbs.org/wgbh/nova/photo51/