Gel electrophoresis is used for

Which of the following steps are involved in the process of recombinant biotechnology? Arrange in correct order.
$I.$ Extraction of the desired gene product
$II.$ Amplification of the gene of interest
$III.$ Isolation of a desired $DNA$ fragment
$IV.$ Ligation of the $DNA$ fragment into a vector
$V.$ Insertion of recombinant $DNA$ into the host
Correct order is:

Southern blotting is done for

What type of method is the $PCR$ technique?

What would happen when one grows a recombinant bacterium in a bioreactor but forgets to add antibiotic to the medium in which the recombinant is growing?

Explain how the synthesis of a gene of interest is performed using $PCR$.