Problem:
In the Meselson-Stahl experiment, 15N-labeled cells were shifted to 14N medium at what is designated as generation 0. In subsequent divisions DNA molecules can result that are N15-N15, N15-N14 or N14-N14.
Required:
Question: For the conservative model of replication, what proportion of 14N-14N would you expect to find after one replication cycle? Show your calculations, but you do not need to write out any explanation.
Question: what would you expect after three replication cycles? Explain thoroughly.