When $DNA$ fragments stained with ethidium bromide are viewed under $UV$ radiation,how do they appear?

After staining,the $DNA$ fragments can be seen on the gel by exposing them to.......... light,which appear as.......... colored bands.

Describe the role of $CaCl_2$ in the preparation of competent cells.

Give the various methods to make bacteria a competent host.

What happens if a foreign $DNA$ fragment is inserted into the coding sequence of the $\beta$-galactosidase enzyme in a plasmid containing the coding sequence for the $\beta$-galactosidase enzyme?

Main steps in the formation of Recombinant $DNA$ are given below. Arrange these steps in a correct sequence.
$A$. Insertion of recombinant $DNA$ into the host cell
$B$. Cutting of $DNA$ at specific location by restriction enzyme
$C$. Isolation of desired $DNA$ fragment
$D$. Amplification of gene of interest using $PCR$
Choose the correct answer from the options given below: