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

Who discovered the synthesis of $DNA$ from $RNA$ in Rous sarcoma virus?

Experiments involving the use of radioactive thymidine to detect the distribution of newly synthesized $DNA$ in the chromosome were performed on which plant?

Choose the correct option regarding the origin of replication $(ori)$.

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 the other strand it is discontinuous.
In the light of the above statements,choose the correct answer from the options given below:

The growth of Okazaki fragments in a $DNA$ strand is .....