For how long should bacteria be cultured in a $^{14}N$ medium after being transferred from a $^{15}N$ medium so that the extracted $DNA$ consists of equal amounts of hybrid $DNA$ and light $DNA$?

Depending upon the chemical nature of the template ($DNA$ or $RNA$) and the nature of nucleic acids synthesized from it ($DNA$ or $RNA$),list the types of nucleic acid polymerases.

Okazaki fragments are formed:

Given below are two statements,one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R).$
Assertion $(A):$ $\text{DNA}$ replication occurs within a small opening of the $\text{DNA}$ helix,referred to as the replication fork.
Reason $(R):$ During transcription,the discontinuously synthesized fragments of $\text{DNA}$ are joined by the enzyme $\text{DNA}$ ligase.
In the light of the above statements,choose the most appropriate answer from the options given below:

In the process of $DNA$ replication,deoxyribonucleoside triphosphates act as:

$A$ bacterium containing fully radioactive $DNA$ is allowed to replicate in a non-radioactive medium for two generations. What percentage of bacteria should contain radioactive $DNA$ (in $\%$)?