The Structure of DNA
DNA: The Genetic Material The instructions for inherited traits are called genes DNA: primary material that causes recognizable, inheritable characteristics in related groups of organisms
Discovering DNA’s Structure Griffith (1928) Discovered that harmless bacteria could cause disease when they were mixed with killed disease-causing bacteria Transformation
Discovering DNA’s Structure Avery (1940’s) DNA is responsible for transformation in bacteria
Discovering DNA’s Structure Hershey & Chase (1950’s) Showed that DNA, not protein, is the genetic material in viruses
Discovering DNA’s Structure Chargaff (1949) showed the base pairs of DNA Adenine with Thymine Cytosine with Guanine
Discovering DNA’s Structure Rosalind Franklin and Maurice Wilkins (1950’s) used x-ray diffraction to determine the structure of DNA Images suggested DNA resembled a tightly coiled helix composed of two chains of nucleotides
Discovering DNA’s Structure Watson and Crick (1950’s) constructed a 3D model of DNA Using information from past experiments determined the DNA was a double helix Won Nobel Prize in 1962
The Shape of DNA A DNA molecule looks like a spiral staircase Composed of two parallel strands of linked subunits called nucleotides
The Shape of DNA A nucleotide has 3 parts: phosphate group, sugar (deoxyribose), and a base The phosphate and sugar link together to form the back bone The bases pair together to connect the two strands
Base Pairs