How do your genes determine your eye color?

1. How do your genes determine your eye color? QOD

2. Section 10-1 Discovery of DNA

3. DNA is The Genetic Material • Evidence in favor of DNA • Frederick Griffith – 1928 • Transformation • Avery, McCarty & MacLeod – 1944 • Hershey & Chase – 1952 • Bacteriophages

4. Mixture of heat-killed S cells and living R cells Heat-killed S cells (control) Living R cells (control) Living S cells (control) LE 16-2 RESULTS Mouse dies Mouse healthy Mouse healthy Mouse dies Living S cells are found in blood sample

5. Section 1 Discovery of DNA Chapter 10 The Hershey-Chase Experiment

6. Draw and label a diagram of DNA. b) How does your DNA store genetic information? QOD

7. Section 10-2 DNA Structure

8. What is DNA? • Deoxyribonucleic acid • Genetic information • Traits • Instructions/blue prints for proteins

9. DNA Structure To return to the chapter summary click escape or close this document.

10. The Structural Model of DNA • Rosalind Franklin (with Maurice Wilkins) • X-ray diffraction • Sugar-phosphate backbones on the side • James Watson and Francis Crick • Double-helix • Nitrogen bases facing inward

11. Make-up of DNA To return to the chapter summary click escape or close this document.

12. Makeup of DNA • Nucleotides (3 parts) • Deoxyribose • Phosphate group • Nitrogenous bases (4 different) • Purines • Adenine (A) • Guanine (G) • Pyrimidines • Cytosine (C) • Thymine (T)

13. Section 2 DNA Structure Chapter 10 DNA Nucleotides

14. Nucleotide Structure • Nucleotides join by bonding a deoxyribose of one nucleotide to the phosphate group of another • Sugar and phosphate = backbone of DNA • Nitrogeneous base stick out to side • Chargaff’s rule • Complementary bases

15. III. DNA Structure • Watson and Crick Model (1953) • DNA is 2 strands • Held together by weak hydrogen bonds • H-bonds only form between certain bases (complementary base pairs) • Double-helix shape

16. Section 2 DNA Structure Chapter 10 DNA Nucleotides

17. Why does DNA replicate itself? When does DNA replicate itself? How does DNA replicate itself? QOD

18. Section 10-3 DNA Replication

19. DNA Replicating To return to the chapter summary click escape or close this document.

20. I. DNA Replication • Steps: • 1) Strands separate • Replication fork • Helicases • 2) Base pairing • DNA polymerase • Complementary base pairing • 3) Bonding of new nucleotides • Covalent bonds • Semiconservative replication

21. Section 3 DNA Replication Chapter 10 DNA Replication

22. DNA Replication

23. Section 3 DNA Replication Chapter 10 Replication Forks Increase the Speed of Replication

24. Results • Results: • Two identical strands of DNA • Each has 1 original half and 1 new half • Accuracy and Repair • Proofreading • Mutations • Cancer

25. Gene Mutations • Point mutations • Substitution • Frameshift mutations • Insertion • Deletion

26. Gene Mutations To return to the chapter summary click escape or close this document.

27. Compare and Contrast DNA to RNA. QOD

28. Section 10-4 Protein Synthesis

29. Introduction • Genes, made of DNA, control traits • DNA contains the information to make proteins • The sequence of bases found in DNA contains the instructions for assembling a chain of amino acids (polypeptide)

30. I. RNA • Made of nucleotides, like DNA • Differences: • Types: • mRNA • tRNA • rRNA

31. Section 4 Protein Synthesis Chapter 10 RNA Structure and Function

32. How is transcription similar to DNA replication? How is it different? QOD

33. Transcription of DNA To return to the chapter summary click escape or close this document.

34. II. Transcription • Production of mRNA molecule • Uses half of the DNA as a template • First step in protein synthesis • Occurs in Nucleus

35. Section 4 Protein Synthesis Chapter 10 Transcription

36. Steps of Transcription • Separation of DNA • Promoters • Formation of complementary RNA • One strand • RNA polymerase • RNA will detach and DNA reconnects • Termination signal

37. Transcription

38. More on Transcription • Promoters – regions of DNA that act as signals to start/stop transcription • RNA editing: • Introns • Exons • Final product: transcripts • mRNA

39. Introduction • Proteins = multiple chains of amino acids • There are 20 different amino acids • Structure of proteins • Primary • Secondary • Tertiary • Quartenary

40. Fig. 2.17a

41. Fig. 2.17b

42. Fig. 2.17c

43. Fig. 2.17d

44. What is the next step in protein synthesis?How is the mRNA read? QOD

45. The Genetic Code • The mRNA is “read” by the ribosome three bases at a time • Codon – 3 consecutive bases that specify a single amino acid • Example: UCGCACGGU Proteins are made by “reading” and “translating” these codons

46. Section 4 Protein Synthesis Chapter 10 Genetic Code

47. Translation • Translation is the decoding of the mRNA molecule into a polypeptide chain • Occurs at the ribosome • Involves mRNA, tRNA, rRNA

48. What is the result of a mutation (point or frameshift) in the sequence if DNA? QOD

49. Section 4 Protein Synthesis Chapter 10 Translation: Assembling Proteins

50. Steps of Translation • mRNA moves to ribosome • Role of tRNA • Each tRNA has an anticodon that is complimentary to mRNA codon • Each type of tRNA carries a specific amino acid • When the codon and anticodon match, an amino acid is brought over to the ribosome • Codon: AUG • Anticodon: UAC