What type of vaccine is the Hepatitis $B$ vaccine?

In the presence of a chromogenic substrate,what color colonies do recombinants and non-recombinants produce,respectively?

Which of the following is $NOT$ included in the downstream processing of recombinant $DNA$ technology?

Assertion : The uptake of $DNA$ during transformation is an active,energy-requiring process.
Reason : Transformation occurs in only those bacteria,which possess the enzymatic machinery involved in the active uptake and recombination.

Select the correct statement.

In the case of polymerase chain reaction $(PCR)$,what are the temperatures required for the following steps?
$A.$ Denaturation
$B.$ Annealing
$C.$ Extension