Question

The steps involved in recombinant DNA technology is illustrated below:
(a) Identify the DNA into which the cut human gene is ligated.
(b) What happens when ‘X’ is inserted into the host cell?

Hint:

Plasmids are commonly used vectors in recombinant DNA technology because they can replicate independently inside bacterial cells.

Answer 1

Step 1: Understanding recombinant DNA technology.
Recombinant DNA technology involves combining a desired gene (from human DNA) with a vector DNA and then introducing it into a host cell for replication and expression.
Step 2: Identify the DNA used for ligation.
The cut human gene is ligated into a plasmid DNA. Plasmids are circular DNA molecules present in bacteria and are commonly used as vectors in genetic engineering.
Step 3: Identify ‘X’.
‘X’ represents the recombinant DNA (recombinant plasmid) formed after the insertion of the human gene into the plasmid.
Step 4: Explain what happens after insertion into host cell.
When ‘X’ (recombinant plasmid) is inserted into the host bacterial cell, it begins to replicate along with the host DNA. The inserted gene is also expressed, leading to the production of the desired protein.
Step 5: Conclusion.
Thus, plasmid acts as the vector for gene insertion, and introduction of recombinant DNA into the host results in cloning and expression of the desired gene.