1. DNA: The Genetic Material

2. Identifying the Genetic Material
Experiments of Griffith and Avery yielded results that suggested DNA was genetic material (1944)

3. Hershey & Chase used the bacteriophage T2 and radioactive labels to show that virus genes are made of DNA, not protein (1952)

4. DNA stores information that tells cells which proteins to make and when to make them

5. The Structure of DNA
Discovered by Watson & Crick in 1953 & received Nobel Prize in 1962 along with Maurice Wilkins

6. DNA  Polymer : Nucleotide  Monomer
Each Nucleotide has 3 parts:
1) 5 carbon sugar  Deoxyribose
2) Phosphate group  PO4
3) Nitrogen Base

9. DNA forms a spiral ladder  Double HelixT G C
Human 30 19
Plant 27 22
Virus 21 28
DNA forms a spiral ladder  Double Helix
Double helix is held together by weak Hydrogen bonds
Erwin Chargaff Discovery Chargaff’s Rule A=T, G=C
Dfgsdg

10. DNA Replication Phase of Cell Cycle? Why replicate?
Step 1: DNA Helicase unzips DNA by breaking weak Hydrogen bonds.
Step 2: DNA polymerase adds nucleotides to exposed nitrogen bases.
Step 3: Two DNA molecules form that are identical to original.

11. DNA is referred to as “Semi-conservative”, Each DNA molecule  1 template & 1 new strand
DNA polymerase proofreads DNA during its replication so that very few errors occur

12. Eukaryotes