1. DNA Replication Copying the genetic code

2. DNA Replication  Unpack the Chromosomes  Unzip the DNA  Base pairing at the replication fork  Leading strand vs Lagging strand

3. Making Copies

5. copycopied during cell division Sister Chromatids (identical copies)

7. Accessing the DNA inactive DNA (deactivated or mitotic) DNA in use

8. Visualization of DNA Packing  For this video, visit: http://www.hhmi.org/biointeractive/dna /DNAi_packaging_vo2.html http://www.hhmi.org/biointeractive/dna /DNAi_packaging_vo2.html http://www.hhmi.org/biointeractive/dna /DNAi_packaging_vo2.html

9. Accessing the DNA

11. DNA Structure

12. Complementary Base Pairing

13. Identical Parent and Daughter Strands

14. Replication Bubbles helicase 5’ 3’ 5’

15. Replication Bubbles 5’ 3’ 5’

16. Replication Bubbles 5’ 3’ 5’

17. Replication Bubbles copies Replication Fork 5’ 3’ 5’

18. Replication Bubbles

19. Releasing the Tension

20.  Topoisomerase (gyrase) cleaves and uncoils DNA ahead of helicase  Single-stranded DNA binding proteins (SSB) prevent DNA from coiling back up

21. DNA Replication Primase RNA primer DNA Polymerase III 5’ 3’ 5’

22. DNA Replication  The leading strands grow toward the replication fork  PROBLEM: DNA polymerase III only works in the 5’-3’ direction. Leading Strands 5’ 3’ 5’

23. DNA Replication 5’ 3’ 5’

24. DNA Replication Lagging Strands  The lagging strands grow away from the replication fork 5’ 3’ 5’

25. DNA Replication 5’ 3’ 5’ DNA Polymerase I DNA Ligase

26. DNA Replication 5’ 3’ 5’

27. DNA Replication continuous & discontinuous Okazaki Fragments 5’ 3’ 5’ DNA Polymerase moves in a 5’ - 3’ direction 5’-3’ chain synthesized continuously 3’-5’ chain synthesized discontinuously Results in a series of Okazaki fragments Later sealed up by DNA ligase

31. The Whole Process in 3D  For this video, visit:  http://www.hhmi.org/biointeractive/dna /DNAi_replication_schematic.html http://www.hhmi.org/biointeractive/dna /DNAi_replication_schematic.html http://www.hhmi.org/biointeractive/dna /DNAi_replication_schematic.html

32. The Whole Process in 3D  For this video, visit: http://www.hhmi.org/biointeractive/dna/ DNAi_replication_vo2.html http://www.hhmi.org/biointeractive/dna/ DNAi_replication_vo2.html

33. Animations  DNA Replication:  http://www.youtube.com/watch?v=4jtmOZaIvS0 http://www.youtube.com/watch?v=4jtmOZaIvS0  McGraw-Hill: DNA Replication & Meselson-Stahl:  http://highered.mcgraw- hill.com/sites/0072437316/student_view0/chapter14/ animations.html# http://highered.mcgraw- hill.com/sites/0072437316/student_view0/chapter14/ animations.html# http://highered.mcgraw- hill.com/sites/0072437316/student_view0/chapter14/ animations.html#  DNA Song:  http://www.youtube.com/watch?v=dIZpb93NYlw http://www.youtube.com/watch?v=dIZpb93NYlw

34. Credits  Molecule drawing created using ChemSketch.  Some from the Pearson or Nelson Biology 12 textbook.  Some images from Wikimedia Commons  Some from unknown sources.