In the Meselson-Stahl experiment, which observation ruled out the conservative model of DNA replication?
A) No completely "heavy" DNA was observed after the first round of replication.
B) No completely "light" DNA ever appeared, even after several replications.
C) The product that accumulated after two rounds of replication was completely "heavy."
D) Completely "heavy" DNA was observed throughout the experiment.
E) Three different DNA densities were observed after a single round of replication.

Question

Quizplus · Accepted Answer

According to the conservative model, after one round of replication, there would be one completely "heavy" DNA molecule and one completely "light" DNA molecule. However, the Meselson-Stahl experiment observed only intermediate-density DNA after the first round of replication, ruling out the conservative model.

In the Meselson-Stahl Experiment, Which Observation Ruled Out the Conservative