1. Hershey Chase Experiment
Illustration of a “Fair Test” in Science

2. What is a “Fair Test”?
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)

3. Hershey Chase Experiment What was the experimental question?

4. Worksheet Hint #1: Some amino acids: Do any of them contain phosphorus
Worksheet Hint #1: Some amino acids: Do any of them contain phosphorus?  (P) Do any of them contain sulfur?  (S)

5. Radioactive sulfur used to create radioactive protein coat

6. What were the results of the Hershey-Chase experiment?
What was their conclusion?

7. D. 1953 - James Watson and Francis Crick propose a model for the DNA molecule

8. 1. Based on x-ray crystallography images prepared by Rosalind Franklin and Maurice Wilkins