Name a few enzymes involved in $DNA$ replication other than $DNA$ polymerase and ligase. Name the key functions for each of them.
$(i)$ Helicase - opens the helix $(ii)$ Topoisomerases - removes the super coiling of $DNA$ $(iii)$ Primase - synthesises $RNA$ primer $(iv)$ Telomerase - to synthesises the $DNA$ of telomeric end of chromosomes
Escherichia coli fully labelled with $15 \mathrm{~N}$ is allowed to grow in $14 \mathrm{~N}$ medium. The two strands of $DNA$ molecule of the first generation bacteria have
For proving the semi conservative mode of replication of $DNA$ , $E-coli$, were first grown in the medium containing ?
$DNA$ polymerase helps in
Given below are two statements :
Statement $I:$
DNA polymerases catalyse polymerisation only in one direction, that is $5^{\prime} \rightarrow 3^{\prime}$
Statement $II:$
During replication of $DNA$, on one strand the replication is continuous while on other strand it is discontinuous.
In the light of the above statements, choose the correct answer from the options given below :
$DNA$ repairing is done by