1. CHAPTER 12: DNA and RNA

2. Review 1.What organelle is known as the “control center” of the cell? 2.What structures are found in the nucleus? 3.What are located on chromosomes? 4.What are chromosomes composed of? 5.How do genes and chromosomes control the activity of the cell?

3. Griffith Experiment

4. Disease-causing bacteria (smooth colonies) Harmless bacteria (rough colonies) Heat-killed, disease- causing bacteria (smooth colonies) Control (no growth) Heat-killed, disease-causing bacteria (smooth colonies) Harmless bacteria (rough colonies) Dies of pneumoniaLives Live, disease-causing bacteria (smooth colonies) Dies of pneumonia Section 12-1 Figure 12–2 Griffith’s Experiment

5. Disease-causing bacteria (smooth colonies) Harmless bacteria (rough colonies) Heat-killed, disease- causing bacteria (smooth colonies) Control (no growth) Heat-killed, disease-causing bacteria (smooth colonies) Harmless bacteria (rough colonies) Dies of pneumoniaLives Live, disease-causing bacteria (smooth colonies) Dies of pneumonia Section 12-1 Figure 12–2 Griffith’s Experiment Transforming factor altered the Rough (harmless) Bacteria into Smooth (harmful) Bacteria

6. Avery, MacCleod, and McCardy Experiment

7. Avery, MacLeod and others Did the same experiment as Griffith except with isolating the biological compounds of Carbohydrates, Lipids, Proteins and DNA to see which when missing did not allow the transformation Only DNA was necessary for the transformation to occur; therefore it is the transforming factor.

8. Hershey and Chase Experiment

9. Bacteriophage with phosphorus-32 in DNA Phage infects bacterium Radioactivity inside bacterium Bacteriophage with sulfur-35 in protein coat Phage infects bacterium No radioactivity inside bacterium Figure 12–4 Hershey-Chase Experiment Section 12-1

10. Bacteriophage with phosphorus-32 in DNA Phage infects bacterium Radioactivity inside bacterium Bacteriophage with sulfur-35 in protein coat Phage infects bacterium No radioactivity inside bacterium Section 12-1 Figure 12–4 Hershey-Chase Experiment

11. Bacteriophage with phosphorus-32 in DNA Phage infects bacterium Radioactivity inside bacterium Bacteriophage with sulfur-35 in protein coat Phage infects bacterium No radioactivity inside bacterium Section 12-1 Figure 12–4 Hershey-Chase Experiment Validated that DNA is the agent of genes

12. Chargaff Rule

13. Percentage of Bases in Four Organisms Section 12-1 Source of DNAATGC Streptococcus29.831.620.518.0 Yeast31.332.918.717.1 Herring27.827.522.222.6 Human30.929.419.919.8 Streptococcus29.831.620.518.0 Yeast31.332.918.717.1 Herring27.827.522.222.6 Human30.929.419.919.8

14. Rosalind Franklin and Maurice Wilkins

15. But we must not forget Rosalind Franklin

16. Watson and Crick

17. Watson & Crick http://www.ted.com/index.php/talks/james_watson_on_how_he_discovered_dna.html

19. A passion to KNOW "You've got to be in it because you are actually curious about something. That's the fundamental. You can't go into science to be famous. You go into science because you are curious. That has to be the driving force." --Watson

20. Evidence of DNA Structure X-Ray Diffraction –Rosalind Franklin and Maurice Wilkins Chargaff base pairing –A- –G- Watson and Crick Final DNA model –Double –Nobel Prize winners in 1962 T C Helix

21. Summary

22. Building block of DNA _____________ are the building block –Consist of: 5-Carbon sugar (Deoxyribose), Phosphate group, and Nitrogenous base: –Adenine and Guanine : _____________ –Thymine and Cytosine: _____________ Sugar and Phosphate groups form __________ while nitrogenous bases ______________ in between. Nucleotides backbone hydrogen bond Purines Pyrimidines

23. PurinesPyrimidines AdenineGuanine CytosineThymine Phosphate group Deoxyribose Figure 12–5 DNA Nucleotides Section 12-1

24. Hydrogen bonds Nucleotide Sugar-phosphate backbone Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Figure 12–7 Structure of DNA Section 12-1

26. Summary of DNA structure

27. I Q #2 1.What is the genetic code? Why is it important? 2.What was Frederick Griffith studying originally? 3.Define Transformation 4.Avery, and colleagues discovered that DNA is the _______________. 5. Hershey and Chase worked with __________. 6. What is the building block of DNA? What is it composed of?

28. 12-2: Chromosomes and DNA Replication A.DNA and Chromosomes a. Prokaryotes ___________and their DNA is found in the cytoplasm. b. It consists of a _____________________ DNA molecule c. This is the cells ______________ d. Eukaryotic DNA is more complicated e. It is not free in the cytoplasm but is contained in the _________ of the cell. f. It forms a _______ of chromosomes not just one g. humans have __, Drosophila have __ and a Sequoia tree have __. lack nuclei large, singular circular chromosome nucleus number 46 8 22

29. 1. DNA Length a. ____ molecules are surprisingly long b. prokaryotes DNA of E. coli is over __ million base pairs long. c. it must be ___________________ that is one-one thousandths it’s size. (see fig. 12-9) d. How does it do this? DNA 4 packed into a space

30. 2. Chromosome Structure a. DNA in ______________ is even more tightly packed. b. Eukaryotic DNA has over _______ DNA base pairs and is measured at over 1 meter of DNA c. It is folded into a tiny _____________ d. How does it do this? e. Eukaryotic DNA contains both DNA and ________(proteins) packed together to form _________. eukaryotic cells 6 billion chromosome histones chromatin

31. 2. Chromosome Structure (cont.) f. Chromatin consists of ____ tightly wrapped around histones to form a _________ structure called a ___________. g. Nucleosomes pack with one another to form a thick fiber and are _________ by a system of ______________. h. During the _________ these fibers are dispersed and __________. i. During _________ they are condensed and coiled into the ________ chromosomes. j. What do nucleosomes do? _____________ _______________________________________ _______ DNA beadlike nucleosome shortened loops and coils cell cycle not visible mitosis visible they are able to fold the DNA into the tiny space of the cell nucleus

32. DNA Supercoiling into Chromosomes Chromosome Supercoils Coils Nucleosome Histones DNA double helix

33. B.DNA Replication Remember what Watson and Crick learned about DNA: - Holds the in the sequence of nucleotides -Is - consists of two parallel strands of sugar-phosphate groups. Pairs of nitrogenous bases link the two strands together, forming a -The Nitrogen (N)-base pairing is because each strand can be used to make the other strand. Genetic code double stranded double helix complementary

34. B.DNA Replication -In ____________ replication begins on one point on the chromosome and ___________ ______________ -In __________ the DNA replication occurs in ________ of places and occurs in ____ _____________ until each chromosome is copied. -The sites where separation and replication occur are called _______________. prokaryotes continues in two directions eukaryotes hundreds both directions replication forks

35. The Structure of DNA = Phosphate = Deoxyribose (5-c sugar) = N-base (A-T) (G-C) Hydrogen bonds

36. Try your own: A A T T T C G A T G G C (Strand 1) (Strand 2) A. This aids in DNA replication. The Replication of DNA T T A A A G C T A C C G Each strand of the double helix serves as a template, or model, for the new strand

37. B. Q: Why does DNA need to replicate? A: C. DNA replication (aka: DNA synthesis) is done with the aid of. The Replication of DNA When a cell divides to form new cells, the DNA must REPLICATE to ensure new cells have a new copy. Enzymes (DNA Polymerase)

38. The Replication of DNA D. The Enzymes: 1. 2. 3. 4. Separate or “unzip” the two strands of the double helix. Insert the appropriate bases. Covalently bond the sugar to the phosphate Proofread the bases to make sure they were paired correctly

39. Interactive DNA Replication A Science Odyssey: You Try It: DNA Workshop Activity A Science Odyssey: You Try It: DNA Workshop Activity

40. DNA Replication Growth Replication fork DNA polymerase New strand Original strand DNA polymerase Nitrogenous bases Replication fork Original strand New strand

41. The Replication of DNA (Summary) E.The steps in DNA replication 1. 2. The Hydrogen Bonds (between N-bases) break and “unzips” the DNA Each strand serves as a template for the attachment of complementary bases

42. http://www.abbysenior.com/biology/dna_protein_synthesis.htm Unzip Base Pairing2 New Strands The Replication of DNA

43. 12-3 RNA and Protein Synthesis DNA holds the genetic code to make DNA How does DNA get the code outside the nucleus? A: DNAmRNAProtein proteins Proteins are made outside the nucleus on ribosomes Cannot leave the nucleus RNA(Ribonucleic Acid) acts as a messenger between DNA and the ribosomes and carries out the process by which proteins are made from Amino Acids.

44. mRNA and DNA interaction RNA DNA RNA polymerase Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only)

45. I. The Structure of RNA A. Similar to DNA with a few differences: DNARNA Strand Sugar Bases Double Stranded Deoxyribose A-T G-C Single Stranded (can form double strand if it folds back on itself). Ribose A-U G-C

46. The Structure of RNA B. 3 types of RNA: 1.mRNA (messenger RNA) 2. tRNA (transfer RNA) 3.rRNA (ribosomal RNA) Copies the code off DNA in the nucleus and brings it out of the nucleus to the ribosomes Carries amino acids to the ribosomes Along with proteins, rRNA makes the subunits of the ribosomes

47. Different Forms of RNA 50S 30S

48. II. Transcription: RNA Synthesis A. Transcription= The process by which a molecule of DNA is copied to a complementary strand of RNA Page 147

49. Transcription: RNA Synthesis B. Steps of Transcription: Step #1: Step #2: RNA nucleotides base pair with complementary DNA nucleotides DNA mRNA RNA polymerase (enzyme) attaches to a sequence of DNA known as the Promotor and separates the 2 strands ATCG ACG U with the help of RNA polymerase

50. Transcription: RNA Synthesis Now try your own: DNA= T T T A G A G A C C G T A T C mRNA= ** Remember, RNA does not have Thymine! A A A U C U C U G G C A U A G

51. Transcription: RNA Synthesis Step #3: Step #4: RNA polymerase terminates (ends) transcription when it reaches the “STOP” site on the DNA The final RNA strand leaves the nucleus through the pores in the nuclear envelope

52. proteins are responsible for: – DNA and RNA control the process of DNA RNA Protein Controlling biochemical pathways(enzymes) Synthesis of lipids, carbohydrates, and nucleotides Cell structure and cell movement making proteins TranscriptionTranslation Protein Synthesis

53. I. THE NATURE OF THE GENETIC CODE A. Review: 1. Proteins are ________________ 2. Proteins are made of monomers known as _________________ 3. There are ___________ different kinds of amino acids 4. Amino acids form ______________ bonds 5. A string of amino acids is known as a _______________ polymers amino acids 20 peptide polypeptide

54. The Nature of the Genetic Code B. DNA contains C. The code is copied onto D. Every E. Each the code to make proteins mRNA in transcription 3 nitrogenous bases on the mRNA makes a codon. codon specifies an amino acid that is to be placed in the polypeptide chain ** the chart on page 303 lists the 64 codons for the amino acids

55. The Genetic Code (p. 303)

56. The Nature of the Genetic Code Example: DNA: T A C C A G C T C A C T mRNA: Amino Acid: F. AAAUUUGGGGGC Methionine “Start” Codon ValineGlutamic Acid “Stop” Codon An amino acid can have more than one codon Example: Glycine GGG, GGA, GGU, GGC

57. II. TRANSLATION A. Translation= B. The_______________ language is ___________________ into ________________ language The decoding of a mRNA into a polypeptide (protein) nucleic acid translated protein

58. Translation KEY PLAYERS Ribosomal RNA ANTICODON

59. Translation Steps of Translation: Step #1: After leaving the nucleus, Step #2: In the cytoplasm, Step #3: First mRNA binds to the ribosome where rRNA is found tRNA picks up amino acids and carries them to the mRNA the anticodon on tRNA attaches to the mRNA codon that it matches. If the mRNA is AUG what will the anticodon be?

60. Step #4: Then Step #5: As each Step #6: Finally, when tRNA continues to match its ANTICODONS with corresponding mRNA CODONS anticodon and codon bind together, a peptide bond forms between the 2 amino acids The ribosome reaches the stop codon on the mRNA the new polypeptide is released

61. Translation

62. Translation part 2

63. http://library.thinkquest.org/C0123260/basic%20knowledge/images/basic%20knowledge/RNA/translation%20steps.jpg

64. 12-4 Mutations Mutations in Genes = A. Point Mutations = change involving a single nucleotide Mutations that occur in individual genes. Can be changes in several or just one nucleotide TYPEDEFINITIONEXAMPLE One base is replaced by another base AGTGGATC TCACCGAG Nucleotide is removedAGTGGATC AGTGATC Nucleotide is addedAGGTGGATC AGGTGGATTC Base substitution Deletion Insertion

65. Substitution Insertion Deletion Gene Mutations: Substitution, Insertion, and Deletion Go to Section: B. ___________________ = codon groupings are shifted after deletion or insertion. Frameshift Mutations

66. Chromosomal Mutations: Involve the movement of large sections of chromosome Deletion Duplication Inversion Translocation

67. Answers 12-1 1.C 2.B 3.A 4.Double helix 5.Watson, Crick 6.Hydrogen bonds 7.Nucleotide 8.Sugar-phosphate backbone 9. Sugar-phosphate Backbone Hydrogen bonds 10.Approx. 28% of the bases would be thymine.

68. Answers 12-2 1.Separates 2.Two; Four 3.Base pairing 4.Original strand 5.New strand 6.Original strand 7.New strand 8.By coiling and folding very tightly, the DNA of a bacterium is able to fit inside the cell. 9. Typically, chromosomal fibers are dispersed and are not visible. During mitosis, however, they become so tightly packed together as to be visible under a light microscope.

69. Answers 12-3 1.Messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA 2.Transcription 3.Polymerase 4.Translation 5.Anticodon DNA Thymine Double stranded Deoxyribose sugar Both DNA & RNA Consist of a long chain of nucleotides RNA Uracil Single stranded Ribose sugar 6. Compare & Contrast

70. Answers 12-3 cont. mRNA  carries protein assembly instructions rRNA  helps assemble proteins tRNA  carries amino acids used in the contruction of proteins 7.

71. Answer 12-3 cont. 8.Answers may vary. Having a sequence of DNA that could be edited into several different mRNA makes it possible for a single gene to produce several different proteins specifically used in different tissues. This allows a cell to carry less genetic material. It also makes it possible for very small changes in DNA sequences to have a large change in gene expression. This is a mechanism for evolutionary change.

72. Answer 12-3 cont. 9.Arginine, tyrosine, and serine 10.During transcription, the DNA would produce mRNA in which the third base is C, not A. Translation, however, would be unaffected bkz the original and the altered codons, CGA and CGC, both specify the amino acid arginine.

73. Answers 12-4 1.Mutations 2.Gene mutations 3.Chromosomal mutation 4.Deletion: involves the loss of all or part of a chromosome 5.Duplication: produces extra copies of parts of a chromosome 6.Inversion: reverses the direction of parts of chromosomes 7.Translocation: occurs when a part of one chromosome breaks off and attaches to another

74. Answers 12-4 cont. 8.Substitution and frameshift mutations are both point mutations, bkz they occur at a single point in the DNA sequence. However, a substitution affects only a single codon, whereas a frameshift mutation affects all the codons that follow the point of mutation.

75. Answers 12-4 cont. 9.Polyploid plants are often larger and stronger. This benefits humans by increasing agricultural production and the food supply. 10.An insertion, or frameshift mutation, has occurred.

76. References http://blogs.sanmathi.org/anasuya/category/ media/