Upload
joleen-mckenzie
View
216
Download
2
Tags:
Embed Size (px)
Citation preview
DNAUnit Two
HISTORICAL DNA EXPERIMENTS
FREDRICK GRIFFITH (1928) Transforming principal of DNA
Bacteria are capable of passing genetic information to other bacteria
PHEOBUS LEVENE (1929) Characterized different forms of nucleic acids: DNA and RNA
Determined nucleic acids are made of: adenine (A), thymine (T), cytosine (C), and guanine (G)
OSWALD AVERY (1944) Determined that DNA is the material in which genes and chromosomes are made.
HERSHEY-CHASE EXPERIMENT (1952) Proteins were not the genetic material, DNA was
ROSALAND FRANKLIN (1951-1953) Research found picture of DNA X-ray crystallography Excluded from large discovery
WATSON AND CRICK (1953) Discovered the “double helix” structure of DNA
Published paper without mentioning Rosalind Franklin (CONTROVERSY)
ERWIN CHARGAFF (1959) Discovered three rules about DNA:
# of guanine equals # of cytosine # of adenine equals # of thymine # of A, T, C, G varies among species
BACKBONE (EDGES) Deoxyribose sugar
Phosphate group
NITROGENOUS BASES (MIDDLE)
Guanine Thymine
Cytosine Adenine