Question: A famous experiment, Matthew Meselson and Franklin Stahl grew E. coli cells in a medium containin…
Show transcribed image text A famous experiment, Matthew Meselson and Franklin Stahl grew E. coli cells in a medium containing only the "heavy" isotope of nitrogen,^15N. These cells were then transferred to a medium with the "light" isotope of nitrogen,^14N. The results of the experiment supported the hypothesis of semiconservative replication, which was proposed by Watson and Crick. Heavy DNA (^15N DNA), hybrid DNA, and light DNA (^14N DNA) can be separated by centrifugation. If cells containing^15N DNA are transferred to a medium with only NH4CI as a nitrogen source, what percent of daughter molecules are composed of hybrid DNA after 4 generations? Predict what percent of daughter molecules would be composed of hybrid DNA if DNA exhibited conservative replication – that is, if a daughter DNA molecule were composed of newly synthesized DNA only.
A famous experiment, Matthew Meselson and Franklin Stahl grew E. coli cells in a medium containing only the "heavy" isotope of nitrogen,^15N. These cells were then transferred to a medium with the "light" isotope of nitrogen,^14N. The results of the experiment supported the hypothesis of semiconservative replication, which was proposed by Watson and Crick. Heavy DNA (^15N DNA), hybrid DNA, and light DNA (^14N DNA) can be separated by centrifugation. If cells containing^15N DNA are transferred to a medium with only NH4CI as a nitrogen source, what percent of daughter molecules are composed of hybrid DNA after 4 generations? Predict what percent of daughter molecules would be composed of hybrid DNA if DNA exhibited conservative replication – that is, if a daughter DNA molecule were composed of newly synthesized DNA only.
