![Page 1: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/1.jpg)
![Page 2: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/2.jpg)
History of DNA ~ReviewHistory of DNA ~Review• Discovery of the DNA double
helix....
A. Dates back to the mid 1800’sB. DNA images become clear during 1950’sC. Rosalind Franklin – took X-ray photos of DNA.D. Watson and Crick - described the DNA molecule from Franklin’s X-ray.
![Page 3: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/3.jpg)
Question:Question:•What is DNA?
![Page 4: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/4.jpg)
Deoxyribonucleic Acid (DNA)
• Genetic material made up of nucleotides (DNA molecule) in a DNA double helix.
• Nucleotide:1. Phosphate group2. 5-carbon sugar3. Nitrogenous bases
![Page 5: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/5.jpg)
DNA Nucleotide
OO=P-O O
PhosphatePhosphate GroupGroup
NNitrogenous baseNitrogenous base (A, G, C, or T)(A, G, C, or T)
CH2
O
C1C4
C3 C2
5
SugarSugar(deoxyribose)(deoxyribose)
![Page 6: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/6.jpg)
DNA Double Helix
NitrogenousNitrogenousBase (A,T,G or C)Base (A,T,G or C)
““Rungs of ladder”Rungs of ladder”
““Legs of ladder”Legs of ladder”
Phosphate &Phosphate &Sugar BackboneSugar Backbone
![Page 7: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/7.jpg)
DNA Double Helix
P
P
P
O
O
O
1
23
4
5
5
3
3
5
P
P
PO
O
O
1
2 3
4
5
5
3
5
3
G C
T A
![Page 8: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/8.jpg)
Nitrogenous Bases• PURINES
1. Adenine (A)2. Guanine (G)
• PYRIMIDINES3. Thymine (T)4. Cytosine (C) T or C
A or G
![Page 9: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/9.jpg)
Base # of
Purines PyrimidinesPairs H-Bonds
Adenine (A) Thymine (T) A = T 2
Guanine (G) Cytosine (C) C = G 3
![Page 10: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/10.jpg)
BASE-PAIRINGS
CG
H-bonds
T A
![Page 11: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/11.jpg)
Chargaff’s Rule• Adenine must pair with
Thymine• Guanine must pair with
Cytosine• Their amounts in a given DNA
molecule will be about the same.
G CT A
![Page 12: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/12.jpg)
Discovery of DNA Discovery of DNA StructureStructure
• Erwin Chargraff showed the amounts of the four bases on DNA ( A,T,C,G)
• In a body or somatic cell: A = 30.3% T = 30.3% G = 19.5% C = 19.9%
![Page 13: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/13.jpg)
Question:•If there is 30%
Adenine, how much Cytosine is
present?
![Page 14: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/14.jpg)
Answer:•There would be 20%
Cytosine.
Adenine (30%) = Thymine (30%)
Guanine (20%) = Cytosine (20%) (50%) = (50%)
![Page 15: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/15.jpg)
QuestionQuestion
• If 15% of the nucleotides in a DNA molecule
contain Guanine, what percentage of the
nucleotides contain each of the other 3 bases?
Explain your reasoning.
![Page 16: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/16.jpg)
AnswerAnswer• If Guanine has 15% then
Cytosine also has 15% Adenine and Thymine will have 35%.
![Page 17: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/17.jpg)
![Page 18: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/18.jpg)
Question:•When and where does DNA
Replication take place?
![Page 19: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/19.jpg)
Synthesis Phase (S phase)• S phase in interphase of the cell
cycle.• Nucleus of eukaryotes
Mitosis-prophase-metaphase-anaphase-telophase
G1 G2
Sphase
interphase
DNA replication takesDNA replication takesplace in the S phase.place in the S phase.
![Page 20: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/20.jpg)
**DNA Replication** How DNA makes a copy of itself
Before a cell divides, its DNA is replicated. Because the two
strands of a DNA molecule have complementary base pairs, the nucleotide sequence of each
strand automatically supplies the information needed to produce its
partner. If the two strands of a DNA molecule are separated, each
can be used as a pattern or template to produce a
complementary strand. Each template and it’s new complement together form a new DNA double
helix, identical to the original.
![Page 21: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/21.jpg)
The ProcessStep 1 ~The double-helix unwinds
separating the two strands (like the two sides of a zipper). With the help of DNA helicase, the hydrogen bonds are broken. The areas where it breaks is known as the replication fork, b/c of the Y shape.
ReplicationReplicationForkFork
Parental DNA MoleculeParental DNA Molecule
3’
5’
3’
5’
![Page 22: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/22.jpg)
The Process Cont..Step 2 ~ The enzyme DNA
polymerase & ligase move along the exposed DNA strand, adding nucleotides to a new DNA strand that’s complementary to the template. Polymerase also “PROOFREADS” to make sure there are no errors and each copy is identical to the original.
Step 3 ~ Two DNA molecules are formed & are identical to the original. Each one contains a new and original strand of DNA
![Page 23: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/23.jpg)
![Page 24: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/24.jpg)
![Page 25: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/25.jpg)
![Page 26: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/26.jpg)
![Page 27: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/27.jpg)
![Page 28: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/28.jpg)
Question:• What would be the
complementary DNA strand for the following DNA sequence?
DNA 5’-GCGTATG-3’
![Page 29: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/29.jpg)
Answer:DNA 5’-GCGTATG-
3’DNA 3’-CGCATAC-
5’
![Page 30: History of DNA ~Review Discovery of the DNA double helix.... A.Dates back to the mid 1800s B.DNA images become clear during 1950s C. Rosalind Franklin](https://reader035.vdocument.in/reader035/viewer/2022062908/5a4d1b947f8b9ab0599c2a7d/html5/thumbnails/30.jpg)
Animation of DNA Replication
• DNA Replication - long