1. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries CHAPTER 11 DNA and Its Role in Heredity

2. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Chapter 11: DNA and Its Role in Heredity DNA: The Genetic Material The Structure of DNA DNA Replication The Mechanism of DNA Replication DNA Proofreading and Repair Practical Applications of DNA Replication

3. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA: The Genetic Material In addition to circumstantial evidence, two experiments demonstrated that DNA is the genetic material. 3

4. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA: The Genetic Material In one, virulent strain pneumococcus bacteria DNA genetically transformed nonvirulent bacteria into virulent bacteria. Review Figure 11.111.1 4

5. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.1 figure 11-01.jpg

6. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA: The Genetic Material In a second, labeled viruses were incubated with host bacteria. Labeled viral DNA entered host cells, producing hundreds of label-bearing viruses. Review Figures 11.2 and 11.311.211.3 6

7. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.2 – Part 1 figure 11-02a.jpg

8. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.2 – Part 2 figure 11-02b.jpg

9. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.3 figure 11-03.jpg

10. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Structure of DNA X-ray crystallography showed that the DNA molecule is a helix. Review Figure 11.411.410

11. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.4 figure 11-04.jpg

12. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Structure of DNA DNA is composed of nucleotides, each containing adenine, cytosine, thymine, or guanine. There are equal amounts of adenine and thymine and equal amounts of guanine and cytosine. Review Figure 11.511.5 12

13. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.5 figure 11-05.jpg

14. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Structure of DNA Watson and Crick proposed that DNA is a double-stranded helix with antiparallel strands, and with bases linked by hydrogen bonding. Their model accounts for genetic information, mutation, and replication functions of DNA. Review Figures 11.6 and 11.711.611.7 14

15. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.6 figure 11-06.jpg

16. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.7 – Part 1 Figure 11.7 - Part 1 figure 11-07a.jpg

17. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.7 – Part 2 figure 11-07b.jpg

18. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA Replication Semiconservative, conservative, and dispersive models for DNA replication were hypothesized. Review Figure 11.811.8 18

19. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.8 figure 11-08.jpg

20. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA Replication Meselson and Stahl’s experiment proved replication of DNA to be semiconservative. A parent strand is a template for synthesis of a new strand. Two replicated DNA helices contain one parent strand and one synthesized strand each. Review Figures 11.9 and 11.1011.911.10 20

21. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.9 figure 11-09.jpg

22. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.10 figure 11-10.jpg

23. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication DNA polymerase catalyzes nucleotides to the 3’ end. Nucleotides are added by complementary base pairing with the template strand. The substrates, deoxyribonucleoside triphosphates, are hydrolyzed as added, releasing energy for DNA synthesis. Review Figure 11.1111.11 23

24. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.11 figure 11-11.jpg

25. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication The DNA replication complex is in a fixed location and DNA is threaded through it for replication. Review Figure 11.1211.1225

26. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.12 figure 11-12.jpg

27. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication Many proteins assist in DNA replication. DNA helicases unwind the double helix, the template strands are stabilized by other proteins. 27

28. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication Prokaryotes have a single origin of replication; eukaryotes have many. Replication for each proceeds in both directions from an origin of replication. Review Figure 11.1311.13 28

29. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.13 figure 11-13.jpg

30. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication An RNA primase catalyzes the synthesis of short RNA primers, and to which nucleotides are added. Review Figure 11.1511.15 30

31. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.15 figure 11-15.jpg

32. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication DNA polymerase action causes the leading strand to grow in the 5’-to-3’ direction until replication of that section of DNA is complete. RNA primer is degraded and DNA replaces it. 32

33. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries The Mechanism of DNA Replication On the lagging strand, growing in the other direction, DNA is made in the 5’-to-3’ direction but synthesis is discontinuous: DNA is added as short fragments to primers, then the polymerase skips past the 5’ end to make the next fragment. Review Figures 11.16, 11.17 and 11.1811.1611.1711.18 33

34. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.16 figure 11-16.jpg

35. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.17 figure 11-17.jpg

36. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figur e 11.18 figure 11-18.jpg

37. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA Proofreading and Repair There is about one error in 10 6 nucleotide bases added in DNA replication, repaired by: proofreading, mismatch repair, and excision repair. DNA repair mechanisms lower the error rate to about one base in 10 9. Review Figure 11.1911.19 37

38. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.19 figure 11-19.jpg

39. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries DNA Proofreading and Repair Although energetically costly and somewhat redundant, DNA repair is crucial to the survival of the cell. 39

40. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Practical Applications of DNA Replication The principles of DNA replication can be used to determine the nucleotide sequence of DNA. Review Figure 11.2011.2040

41. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.20 – Part 1 figure 11-20a.jpg

42. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.20 - Part 2 Figure 11.20 – Part 2 figure 11-20b.jpg

43. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Practical Applications of DNA Replication The polymerase chain reaction technique uses DNA polymerases to repeatedly replicate DNA in the test tube. Review Figure 11.2111.2143

44. Chapter 11: DNA and Its Role in Heredity Exit Next Previous Home Discussion topics Chapter summaries Figure 11.21 figure 11-21.jpg