The enzyme $DNA$ polymerase in $E.coli$ is a $DNA$ dependent polymerase and also has the ability to proof-read the $DNA$ strand being synthesised. Explain. Discuss the dual polymerase.

Who used heavy nitrogen $N^{15}$ for proving semiconservative way of $DNA$ replication

Which of the following statement is correct regarding the process of replication in $E$.coli?

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

Give scientific reasons : $DNA$ polymerase plays a dual function during $DNA$ replication.