Pulse Chase Primer: The Meselson-Stahl Experiment
This activity can be used in conjunction with the short film The Double Helix. It introduces students to the classic experiment by Matthew Meselson and Franklin Stahl, which revealed that DNA replication follows the semiconservative model.
In 1958, Meselson and Stahl published the results of a pulse-chase experiment to determine how cells replicate their DNA. Students will first read about how the experiment was conducted and describe the predicted results based on three possible models of DNA replication. They then evaluate the actual experimental results.
Student Learning Targets
Interpret experimental evidence to distinguish between different models of DNA replication.
Describe the semiconservative model of DNA replication.
conservative replication, dispersive replication, experiment, nucleotide, radioactive, replication, semiconservative replication
Meselson, Matthew, and Franklin W. Stahl. “The Replication of DNA in Escherichia coli.” Proceedings of the National Academies of Science 44, 7 (1958): 671–682. https://doi.org/10.1073/pnas.44.7.671.
The resource is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International license. No rights are granted to use HHMI’s or BioInteractive’s names or logos independent from this Resource or in any derivative works.
HS-LS1-1, HS-LS3-1; SEP2, SEP4
AP Biology (2019)
IST-1.M; SP2, SP3, SP4
IB Biology (2016)
Common Core (2010)
Vision and Change (2009)
CC2, CC3; DP1, DP3