申論題

7. Consider a phage particle containing a small linear, single-stranded DNA molecule. Its replication mode is studied by centrifugation to equilibrium in CsCl. Its density in CsCl is 1.714 g/cm³ . The density for double-stranded DNA is 1.700 g/cm³ . Phage having ¹⁴C-labeled DNA infects the bacterium in medium containing ³H. Samples are taken at various times, DNA is isolated, and each sample is centrifuged. The results shown in Figure on right are obtained. (4%)