1. The Molecule of Life

2. What are the different DNA Nitrogen Bases 1.Purines – double ring structure. AdenineGuanine

3. 2.Pyrimidines – single ring structures CytosineThymine

4. DNA Structure The DNA structure is shaped like a spiral stair case: Double helix

5. DNA REPLICATION Replication is the process where DNA makes an exact copy of itself.

6. If you were to replicate DNA why would you do it, and how would you do it?

7. JQ: Your pet dog stepped on a sharp rock and got a cut. Be as detailed as you can in explaining what happens next in the area of the wound. Need your textbooks!

9. DNA REPLICATION Dispersive Replication

10. DNA REPLICATION Conservative Replication

11. DNA REPLICATION Semi-Conservative Replication

12. DNA REPLICATION Meselson & Stahl Create theMost Beautiful Experiment in Molecular Biology Meselson & Stahl Create the Most Beautiful Experiment in Molecular Biology

13. What do the results tell us? Hypothesis: Semi-Conservative

14. What do the results tell us?

15. General Ovewrview for DNA Replication 1.The two DNA strands separate (dark blue) 2.Each open strand serves as a template for the new strand (light blue) 3.Complimentary bases are added. How is this all possible? What is doing the work?

16. What are the steps of DNA REPLICATION

17. What can you tell me/ What do you notice about this DNA? Strands run in opposite Directions - they are Antiparallel 5’ (five prime) end - has Phosphate on end 3’ (three prime) end - has Hydroxyl group attached

18. Replication in Real Time Replication Broken Down

19. DNA REPLICATION 1. DNA Helicase (enzyme) splits open double strand at origin and unwinds DNA. SSB’s keep the strand open. 2. RNA primase gets strand ready for DNA Polymerase (enzyme) to attaches free floating nucleotides in a 5’ to 3’ position on both strands. Stands are copied in one direction.

20. Leading Strand – is copied in one direction continuously. DNA REPLICATION Lagging Strand –is looped around and copied in fragments (okazaki fragments). Okazaki fragments are linked together by an enzyme called ligase.

21. DNA Replication Stats 1 strand of DNA ~ 150,000,000 base pairs 50 base pairs copied per second 834 molecules working at the same time! Humans have 46 pieces of DNA in their cells.

22. What’s the next question biologists asked?

23. Protein Synthesis Process of making proteins

24. Players Involved 1. mRNA – messenger RNA, reads message from DNA

25. 2. tRNA – transfer RNA, transfers amino acids

26. 3. rRNA – ribosomal RNA, joined with proteins to make up the ribosome (protein factory of the cell) Many, many, many enzymes are involved in this process as well.

27. Nucleic Acids - RNA Monomer Unit – Nucleotide Monomer Unit – Nucleotide Ribose Sugar Ribose Sugar Phosphate Group Phosphate Group Nitrogen Base Nitrogen Base Sugar N. Base P

28. RNA Nitrogen Bases 1.Purines – double ring structure. AdenineGuanine

29. 2.Pyrimidines – single ring structures RNA Nitrogen Bases CytosineUracil

30. RNA Structure The RNA is single stranded

31. Protein Synthesis Stages Transcription – the process of obtaining info. from the DNA on how to make the protein. DNA mRNA Translation – the process of using the information (mRNA) to construct the protein. Translation – the process of using the information (mRNA) to construct the protein.

32. Protein Synthesis Transcription

33. Why do fireflies glow?

34. Protein Synthesis Translation

35. Now that we know how protein synthesis works, what is the next question? How is it controlled?

36. i ß-gal 1 2