Identify the correct sequence of steps in the Polymerase Chain Reaction $(PCR)$.

Which of the following range of temperature is required for denaturation,annealing of primer,and primer extension of $PCR$ respectively?

Which of the following statements are correct with respect to $DNA$ separation, isolation and visualization?
$A$. The cutting of $DNA$ is done by molecular scissors.
$B$. The $DNA$ fragments separate according to their size in an agarose gel, upon electrophoresis.
$C$. The separated $DNA$ fragments can be seen without staining when exposed to $UV$ light.
$D$. The separated $DNA$ fragments, when stained with ethidium bromide, can be seen in visible light.
Choose the correct answer from the options given below:

Which of the following method$(s)$ is used to introduce foreign $DNA$ into host cells?

In the purification process of recombinant $DNA$ technology,what does the addition of chilled ethanol precipitate?

In the context of blue-white screening,non-recombinant bacterial colonies appear blue in contrast to white recombinant colonies because: