What do '$X$' and '$Y$' represent in the given figure of a stirred-tank bioreactor?

Match the columns:

Column-$I$	Column-$II$
$(a)$ Ethidium Bromide	$(i)$ Agrobacterium
$(b)$ Ti plasmid	$(ii)$ Tetracycline
$(c)$ $PvuI$	$(iii)$ Gel electrophoresis
	$(iv)$ Ampicillin

Which of the following bacteria is a close relative of $Salmonella$?

Match the following columns:

Column-$I$	Column-$II$
$(a)$ $Salmonella$	$(1)$ $Ti$ plasmid
$(b)$ $E. coli$	$(2)$ Thermostable $DNA$ polymerase
$(c)$ $Agrobacterium$ $tumefaciens$	$(3)$ Plasmid for first $r-DNA$
$(d)$ $Thermus$ $aquaticus$	$(4)$ $EcoR I$

Which of the following statements is not true?
$I.$ $DNA$, being a hydrophilic molecule, cannot pass through cell membranes.
$II.$ $Agrobacterium$ $tumefaciens$ delivers a piece of $DNA$ known as $'T-DNA'$ in the $Ti$ plasmid, which transforms normal plant cells into tumour cells to produce chemicals against pathogens.
$III.$ Retrovirus, adenovirus, and papillomavirus are also now used as cloning vectors in animals because of their ability to transform normal cells into cancerous cells.
$IV.$ In genetic engineering, $DNA$ from different sources are cut with the same restriction enzymes so that both $DNA$ fragments have the same kind of sticky ends.
Choose the correct option.

Give differences between $PCR$ and plasmid.