1. FINDING DNA

2. Proof of DNA as Genetic Material
Was the genetic material protein or DNA?
Mendel (peas) and Morgan (flies) did not know it was DNA. Worksheet links
Bozeman Biology: DNA and RNA Part I Bozeman Biology: DNA and RNA Part II

3. Frederick Griffith
A medical officer was trying to find a vaccine against pneumococcus

4. Rough and Smooth Pneumococcus

5. Griffith 1920’s
Streptococcus pneumoniae used to show a “transforming factor”

6. Griffith’s Conclusion
Some material in the heat-killed S strain that was responsible for “transforming” the R-strain into a lethal form
transformation = passing the inheritance factor from one organism to another
THIS TRANSFORMING FACTOR WAS LATER FOUND TO BE DNA

7. Oswald Avery 1944
He had reported that DNA, not protein (which was believed at the time), was the hereditary substance (transforming material).
Studied medical research

8. Oswald Avery 1940’s

9. Avery’s Conclusion
Removed DNA, RNA, protein from S-strain pneumococcus
AVERY PROVED THAT DNA WAS THE TRANSFORMING MATERIAL

10. Alfred Hershey and Margaret Chase 1953
Showed that the hereditary material in bacteriophage viruses is DNA.
DNA in water

11. Hershey-Chase

12. Radioactive S35 in protein
Hershey-Chase Bacteriophages Youtube
McGraw-Hill Hershey-Chase Experiment
Radioactive P32 in DNA
Radioactive S35 in protein

13. Hershey-Chase
CONCLUSION –
DNA is genetic material because (32P) nucleic acid not (35S) protein guides viral replication

14. Bacteriophages (“bacteria-eaters”)
Mostly made of just protein coat and DNA

15. Virus Examples
HIV Virus
Cold Virus
Bird Flu Virus
Ebola Virus

16. Herpes Virus

17. Bacteriophage Structure

18. Virus: Are they Alive? Viruses can only replicate in a living host.
"Viruses straddle the definition of life. They lie somewhere between supra molecular complexes and very simple biological entities. Viruses contain some of the structures and exhibit some of the activities that are common to organic life, but they are missing many of the others.”
Dr. Mark Young of MSU youtube (4:00)

19. Bacteriophage Lytic Infection
Attach to host
2. Insert DNA
3. Make and assemble DNA parts
4. Lyse (burst)
EXAMPLES:
Cold
Flu

20. Lysogenic Infection
BIOL 230 Lecture Guide - Lysogenic Life Cycle of a Temperate Bacteriophage (animation link)
1. Virus lands on host.
2. Virus injects DNA into host.
3. Virus DNA attaches to host DNA = prophage.
4. Virus Prophage will become lytic when conditions are favorable (you are sick, tired).

22. Lysogenic Cycle Animation
Animation Quiz 2 - Lamda Phage Replication Cycle
EXAMPLES: HERPES HIV
CHICKEN POX

23. Click on “Journey into DNA”
NOVA Online | Cracking the Code of Life | Journey into DNA (keep clicking on “zoom” + button)
View for extra credit
Write 10 things you learned about DNA

24. What is the structure of DNA?
It is a nucleic acid
Polynucleotide = Made of long chains of Nucleotides

25. DNA Nucleotide O O=P-O N CH2 O C1 C4 C3 C2 Phosphate Group
Nitrogenous base
(A, G, C, or T)
CH2 O C1 C4 C3 C2 5
Sugar
(deoxyribose)

26. DNA Structure
NUCLEOTIDE
POLYNUCLEOTIDE

27. A Nucleotide MADE OF: Sugar Phosphate (A) (G) (T) (C) Base
Deoxyribose sugar
PO4
4 kinds:
(A) (G) (T) (C)
(names on next slide)

28. 4 Types of Base Pairs
A = adenine
T = thymine
C = cytosine
G = guanine
NOW SING THE DNA SONG

29. Nitrogenous Bases PURINES -2 rings 1. Adenine (A) 2. Guanine (G)
PYRIMIDINES -1 ring
3. Thymine (T)
4. Cytosine (C)
A or G
T or C

30. Deoxyribonucleic Acid
DNA
Deoxyribonucleic Acid
(Get out colored pencils)

31. DNA Double Helix “Rungs of ladder” Nitrogenous Base (A,T,G or C)
“Legs of ladder”
Phosphate &
Sugar Backbone

32. DNA backbone
Sugar
Phosphate

33. DNA Structure Rungs of the Ladder: Backbone: Various orders of
A, T, C, G
Backbone:
Sugar and phosphates
Alternate

34. DNA Double Helix P O 1 2 3 4 5 P O 1 2 3 4 5 G C T A

35.  National DNA Day, April 25, 2009
DNA SONG AND VIDEO

36. What’s RNA?
Ribonucleic Acid
Three types:
mRNA
tRNA
rRNA

37. DNA RNA Comparing DNA and RNA Double stranded Sugar = deoxyribose
Bases: A-T, C-G
Found only in nucleus
Can repair itself
RNA
Single stranded
Sugar = ribose
Bases: A-U, C-G
Found in and out of the nucleus
Cannot repair itself

38. RNA DNA

39. Pretty Similar
Uracil
Thymine

40. DNA RNA Both Single stranded molecule Contains uracil
Contains ribose sugar
- Found in nucleus and cytoplasm
Made of nucleotides
- Contain adenine, guanine and cytosine
Contains Thymine
Contains deoxyribose sugar
Double stranded molecule
- Found only in nucleus

41. Bozeman Biology DNA and RNA Part 1
Griffith, Avery, Hershey and Chase, Watson and Crick, pro and eukaryotic chromos
Bozeman Biology DNA and RNA part 2
DNA replication
Transformation
Protein synthesis

42. Relative Proportions (%) of Bases in DNA Organisms A T G C
Human
Chicken
Grasshopper  
Sea Urchin
Wheat
Yeast
E. coli

43. Question: If there is 30% Adenine, how much Cytosine is present?
HINT: A –T and C - G

44. Answer: There would be 20% Cytosine. Adenine (30%) = Thymine (30%)
Guanine (20%) = Cytosine (20%)
Total of 100%

45. Chargaff’s Rules
the amount of (A)denine will always equal the amount of (T)hymine
And
the amount of (G)uanine will always equal the amount of (C)ytosine.
HOT!!!

46. Nitrogenous Bases Why does A bond only with T and C only with G?
What do you notice?

47. Nitrogenous Bases T and C are single-ring Pyrimidines
A and G are double-ring
Purines
A single bonds with a
double

48. 2 chains of nucleotides bind to form a DNA molecule
Hydrogen bonds form between the nitrogenous bases to join the 2 chains together
The sugar and phosphate group together is known as the sugar-phosphate backbone

49. ENZYMES FOR DNA REPLICATION
Helicase = separates 2 DNA strands (breaks H bonds)
Primase=RNA primers at INITIATION

50. Topoisomerase = unwinding DNA
REPLICATION ENZYMES
Topoisomerase = unwinding DNA
DNA Polymerase = Adding of DNA nucleotides ELONGATION (proofread and repair)

51. DNA REPLICATION ENZYMES
LIGASE= Binds the Okazaki fragments
Watch the enzymes in DNA Replication Animation

52. AT and C-G Base Pairing DNA Replication simple version) (link)
Media Showcase (cool animation link)
Detailed Replication Link

54. in tons of combinations makes our genetic code
DNA STRUCTURE
A-T
C-G
in tons of combinations makes our genetic code

55. DNA Replication Animation click here
Hi!...Still Awake?
DNA Replication Animation click here

56. What is the complementary base sequence on the other strand of the DNA?
A T T G C C C T A A
T A A C G G G A T T

57. The Race is On!
To Determine the Structure of the DNA molecule.

58. DNA Geek
Rosalind Franklin was an English chemist who was working in an X-ray crystallography lab in Paris, France in 1951.
FAMOUS PHOTO 51
(correct orientation of DNA)

59. Linus Pauling American biochemist suggested helix (spiral)shape
Most famous for Vitamin C prevents colds

60. DNA Geek
Linus Pauling was a Caltech chemist (USA), who in 1951 had discovered the alpha helical nature of protein structure.
I remember his books: Vitamin C and the Common Cold and Cancer and Vitamin C also
The Nature of the Chemical Bond and protested nuclear testing

61. DNA Geeks
James Watson, a biologist from Indiana University, and Francis Crick, a physicist, were working at the Cavendish Lab in Cambridge, England Nobel Prize for structure of DNA

65. Watson and Crick’s Wire Model
DOUBLE HELIX
First put the nitrogenous bases on the outside

66. DNA Geek

67. DNA Base Pairs
Adenine with Thymine
Guanine with Cytosine

68. X ray Diffraction

69. Franklin’s Suggestion

70. DNA Bases

80. Beadle and Tatum

82. Happy DNA DAY
The day commemorates the completion of the Human Genome Project in April 2003, and the discovery of DNA's double helix. DNA Song
NOVA | Ghost in Your Genes | PBS