In the process of $DNA$ replication, the mechanism where two strands separate and each serves as a template for the synthesis of a new strand is known as .......

Which enzymes join the discontinuously synthesized $DNA$ fragments?

Ten $E. coli$ cells with $^{15}N$-dsDNA are incubated in a medium containing $^{14}N$ nucleotides. After $60$ minutes, how many $E. coli$ cells will have $DNA$ totally free from $^{15}N$ (in $cells$)?

Which enzyme joins the discontinuously synthesised fragments during $\text{DNA}$ replication?

Which bond does $DNA$ helicase break in $DNA$?

Bacteria were grown in a medium containing a heavy isotope of nitrogen $(^{15}N)$ for many generations,and all their $DNA$ contained only heavy nitrogen. $A$ bacterium of this type was transferred to a normal medium and allowed to duplicate. After two divisions,the distribution of heavy $DNA$ is likely to be: