In the Meselson Stahl experiment, E. coli was grown for many generations in a me
ID: 171568 • Letter: I
Question
In the Meselson Stahl experiment, E. coli was grown for many generations in a medium "heavy" nitrogen^15 N. Once the bacterial DNA was uniformly labeled, the bacteria were transferred to a medium containing the "light" nitrogen, ^14N. After ONE round of replication, DNA was extracted and subjected to density gradient centrifugation in cesium chloride. Upon inspection, there was only a single band of intermediate density DNA in the gradient. This proved that DNA replication CANNOT be conservative dispersive semiconservative conservative of dispersive continuous.Explanation / Answer
Answer is Dispersive replication.
Dispersive replication would result in double-stranded DNA with both strands having mixtures of 15N and 14N DNA, either of which would have appeared as DNA of an intermediate density.