Semiconservative Replication

Phosphorus is required to synthesize the deoxyribonucleoside triphosphates used in DNA replication. A geneticist grows some E. coli in a medium containing nonradioactive phosphorus for many generations. A sample of the bacteria is then transferred to a medium that contains a radioactive isotope of phosphorus (32P). Samples of the bacteria are removed immediately after the transfer and after one and two rounds of replication. Assume that newly synthesized DNA contains 32P and the original DNA contains nonradioactive phosphorus.What will be the distribution of radioactivity in the DNA of the bacteria in each sample?• One strand has 32P incorporated.• 50% of the DNA molecules have 32P in one strand.• No 32P incorporated into the DNA.• 50% of the DNA molecules have 32P in both strands.• Both strands have 32P incorporated.

What is meant by the semiconservative nature of DNA?