1. DNA OR Why you look like your parents!!

2. Frederick Griffith

3. Experiment by Griffith See page 288 in your book See page 288 in your book Smooth is a pathogen Smooth is a pathogen Rough is harmless Rough is harmless Heat killed pathogen mixed with live harmless bacteria caused mice to diewhy? Heat killed pathogen mixed with live harmless bacteria caused mice to diewhy? Think about what happens in your body!!! Think about bird flu!!!! Think about what happens in your body!!! Think about bird flu!!!! Transformation Transformation

4. Oswald Avery

5. Experiment from Avery Created a juice from the heat-killed bacteria of Griffith. Created a juice from the heat-killed bacteria of Griffith. Treated the juice with different enzymes that would destroy one type of molecule at a time. Treated the juice with different enzymes that would destroy one type of molecule at a time. Injected micethe juice that was treated with DNA destroying enzyme did NOT kill the miceall the other tests did kill the miceDNA was the factor that caused transformation in bacteria. Injected micethe juice that was treated with DNA destroying enzyme did NOT kill the miceall the other tests did kill the miceDNA was the factor that caused transformation in bacteria.

6. Hershey-Chase Experiment

7. Bacteriophage

8. Was it the protein coat or inner DNA core that was the hereditary material??? Was it the protein coat or inner DNA core that was the hereditary material??? Grew phages in radioactive P & S Grew phages in radioactive P & S Proteins have lots of S but very little P in their chemical makeup. Proteins have lots of S but very little P in their chemical makeup. DNA has lots of P, but no S. DNA has lots of P, but no S. Look at page 290 in your book. Look at page 290 in your book. Radioactive P found in bacteria prey. Radioactive P found in bacteria prey. Evidence that DNA is hereditary material. Evidence that DNA is hereditary material.

9. Purines and Pyrimidines

10. Erwin Chargaff

11. Chargaffs Rules % of Guanine equals % Cytosine in DNA at all times % of Guanine equals % Cytosine in DNA at all times % of Thymine equals % Adenine in DNA at all times % of Thymine equals % Adenine in DNA at all times All organisms from bacteria to bananas to plants to humans obey these rules. All organisms from bacteria to bananas to plants to humans obey these rules. If A is 14% in DNA, what % is C % ? If A is 14% in DNA, what % is C % ?

12. Rosalind Franklin

13. Watson and Crick James Watson James Watson Francis Crick Francis Crick

14. James Watson is still alive!!!! The instant I saw the picture (of the X-ray of DNA by Rosalind Franklin) my mouth fell open and my pulse began to race!! The instant I saw the picture (of the X-ray of DNA by Rosalind Franklin) my mouth fell open and my pulse began to race!!

15. Double Helix

16. DNA Twisted Ladder or spiral staircase. Twisted Ladder or spiral staircase. Hydrogen bonds hold the purines and pyrimidines together. A-T C-G Hydrogen bonds hold the purines and pyrimidines together. A-T C-G 3 hydrogen bonds between G and C 3 hydrogen bonds between G and C 2 hydrogen bonds between T and A 2 hydrogen bonds between T and A This is termed base pairing. This is termed base pairing. Chargaffs rules apply!!! Chargaffs rules apply!!! Deoxyribose Nucleic Acid Deoxyribose Nucleic Acid