Describe in short about $RNA$.

(N/A) $RNA$ (Ribonucleic acid) is a polymer of nucleotides. Each nucleotide consists of a nitrogenous base,a pentose sugar (ribose),and a phosphate group.
The presence of a $2'-OH$ group on every ribose sugar in $RNA$ makes it a reactive group,which renders $RNA$ labile and easily degradable.
$RNA$ was the first genetic material. There is sufficient evidence to suggest that essential life processes,such as metabolism,translation,and splicing,evolved around $RNA$.
$RNA$ functioned as both a genetic material and a catalyst. Certain biochemical reactions in living systems are still catalyzed by $RNA$ (ribozymes) rather than protein enzymes.
Because $RNA$ was reactive and unstable as a catalyst,$DNA$ evolved from $RNA$ with chemical modifications (specifically the loss of the $2'-OH$ group) to become more stable.
$DNA$ is double-stranded and possesses a complementary strand,which allows for a repair mechanism,further ensuring its stability as the primary genetic material.