In which year were the two enzymes responsible for restricting the growth of bacteriophage in $E. coli$ isolated?

Cutting of a piece of $DNA$ from a plasmid was done with the help of $...A...$ enzymes,popularly known as $...B....$ Here $A$ and $B$ can be

Which one of the following is indispensable in genetic engineering?

Refer to the following statements for agarose-gel electrophoresis :
$(a)$ Agarose is a natural polymer obtained from sea-weed.
$(b)$ The separation of $DNA$ molecules in agarose-gel electrophoresis depends on the size of $DNA$.
$(c)$ The $DNA$ migrates from negatively-charged electrode to the positively-charged electrode.
$(d)$ The $DNA$ migrates from positively-charged electrode to the negatively-charged electrode.
Choose the most appropriate answer from the options given below :

The two antibiotic resistance genes on vector $pBR322$ are for

During 'gene cloning',which is called a gene taxi?