The stirrer in a stirred-tank bioreactor facilitates:

Which of the following statements is incorrect?

$I. ... A...$ is the ability of a cell to take up foreign $DNA$.
$II.$ The cell is treated with a specific concentration of a divalent cation such as $... B...$ to increase the pore size in the cell wall.
$III.$ In $...C...$ method,recombinant $DNA$ is directly injected into the nucleus of an animal cell.
The most appropriate option regarding $A, B$ and $C$ is:

What is the first step in the Southern Blotting technique?

In this technique,large quantities of biotechnological products such as antibiotics,vaccines,and enzymes are produced by maintaining and growing only the desired microbes/eukaryotic cells in a sterile environment.

Which enzyme is responsible for the replication of recombinant $DNA$ in the host?