$A$ set of bacterial clones,each containing a plasmid or phage,is called

Polymerase chain reaction employs

In the restriction endonuclease $Eco RI$,what does the part '$co$' stand for?

$A$ : $DNA$ ligase plays an important role in recombinant $DNA$ technology.
$R$ : The linking of antibiotic resistance gene with plasmid vector became possible by enzyme $DNA$ ligase.

Restriction endonucleases are

In cloning vectors,antibiotic resistant genes are helpful for