Hershey Chase Experiment
Illustration of a “Fair Test” in
Science
What is a “Fair Test”?
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Tool to compare two or more competing
hypothesis
Must employ criteria of the natural world
Must not be biased toward either
hypothesis (Could support either)
Hershey Chase Experiment
What was the experimental question?
Worksheet Hint #1:
Some amino acids:
Do any of them contain phosphorus? (P)
Do any of them contain sulfur? (S)
Radioactive sulfur used to create
radioactive protein coat
What were the results of the
Hershey-Chase experiment?
What was their conclusion?
D. 1953 - James Watson and Francis Crick
propose a model for the DNA molecule
1. Based on x-ray crystallography images
prepared by Rosalind Franklin and Maurice
Wilkins