(i) Name the organism in which the vector shown in inserted to get the copies of the desired gene.
(ii) Mention the area labelled in the vector responsible for controlling the copy number of the inserted gene.
(iii) Name and explain the role of a selectable marker in the vector shown.

Explanation

(i) Esherichia coli
(ii) Origin of replication 'Ori' controls copy number of inserted gene.
(iii) The selectable markers are `amp^(R)` (resistance to ampicillin) and tetR (resistance to tetracycline). Selectable markers help to select the host cells which contain the vector and eliminating non-transformants.
If a foreign DNA ligates at the BamHI site of tetracycline resistance gene in the vector pBR322) the recombinant plasmid loses the tetracycline resistance due to insertion of DNA. It can still be selected out from non-recombinant.