$A$: Kornberg enzyme is associated with the removal of primers and thyminedimer.

$R$: $DNA$ polymersase I does exonuclease activity in $5^{\prime} \rightarrow 3^{\prime}$ and $3^{\prime} \rightarrow 5^{\prime}$ directions.

In terms of $DNA$ and $RNA$ structure, what is a nucleotide?

$X$ -ray diffration data produced by …….. and……..

"Cytochimeras'' means