From Gene to Protein: A Historical Perspective "Replication of DNA"

What were the three models of DNA replication under investigation in the 1950's?

You should be able to describe and define:
Conservative
Semiconservative
Dispersive

Watch the animation from the DNA learning center to learn more about the three models
http://www.dnalc.org/view/15880-Models-of-DNA-replication.html


How might you test to determine which model is the correct one?
Assume you have the following materials in your laboratory.  Design an experiment using these materials.  You must justify your choice of organism and isotopes.  You will share your information on a whiteboard with the group.

1. An experimental organism of your choice
2. Your choice of radioactive isotopes (e.g. ¹⁴C, ¹⁴N, ¹⁵N, ³²P)
3. Test Tubes
4. Food/Growth media for organisms
5. A Centrifuge

Meselson & Stahl did an experiment to determine which of the 

models for DNA replication was actually correct

Short animation (from McGrawHill)

DNA from the beginning, Module 20 all about DNA replication and the Meselson Stahl experiment.