In Meselson-Stahl Experiment, they first grew E. coli in the medium with 15N, a heavy isotope of nitrogen, and then moved the E. coli in the medium with 14N for several generations. Below is a figure showing multiple possible band patterns for the result of experiment. The two leftist panels show the band pattern for E. coli growing in the medium with 15N and 14N for a long time, respectively. Given that the DNA duplication follows the semiconservative model, what would be the expected patterns for E. coli that was moved from the medium with 15N to the medium with 14N for two generations of replication?

Then try StudyFetch, the AI-powered platform that can answer your questions and teach you more about it!