$A$ gene library or $DNA$ library contains a collection of:

Agarose is a natural polymer extracted from

Which of the following foreign $DNA$ cannot multiply within a host cell?

Which metal is used in particle bombardment (biolistics) for gene transfer?

Consider the following statements:
$I.$ $A$ soil-inhabiting plant bacterium,$Agrobacterium \; tumefaciens$,a pathogen of several dicot plants,is able to transfer a piece of $DNA$ known as $T-DNA$.
$II.$ The $T-DNA$ causes tumours.
$III.$ Tumour formation is induced by $Ti-plasmid$.
Which of the statements given above are correct?

Where does the replication of a plasmid start?