The Hershey-Chase Experiment
Legend:
Illustration of the 1952 experiment connecting DNA and heredity.
Side by side experiments are performed with separate bacteriophage
(virus) cultures in which either the protein capsule is labeled with radioactive
sulfur or the DNA core is labeled with radioactive phosphorus.
- The radioactively labeled phages are allowed to infect bacteria.
- Agitation in a blender dislodges phage particles from bacterial cells.
- Centrifugation concentrates cells, separating them from the phage particles
left in the supernatant.
Results:
- Radioactive sulfur is found predominantly in the supernatant.
- Radioactive phosphorus is found predominantly in the cell fraction,
from which a new generation of infective phage can be isolated.
Conclusion: The active component of the bacteriophage that transmits
the infective characteristic is the DNA. There is a clear correlation between
DNA and genetic information.
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