Describe the formation of recombinant DNA by the action of EcoRI.

OR

Describe the process of amplification of “gene of interest” using PCR technique

5' - G A A T T C - 3'
3' - C T T A A G - 5'
This is the recognition site for E coli.
Restriction endonuclease cuts at specific cleavage sites.
EcoRI cleaves the sequence between G and A. This generates overhanging part in the DNA sequences called sticky ends. Sticky ends are later ligated with the counterpart by ligation.

OR

The three steps involved in polymerase chain reaction (PCR) are denaturation, annealing, and extension

Denaturation: The temperature is set to between 90-95°C to break hydrogen bonds of DNA. The process takes place for up to 1 min.

Annealing: The temperature is now between 30-65°C. Time taken is about 1 minute. The two primers i.e, forward primer and reverse primers anneal.

Extension: The temperature is set to 70°C for a minute. DNA polymerises and the synthesis of new strands occurs.