Question

If you want to recover many copies of the target DNA, you will choose a vector
A. Which does not have the origin of replication
B. Which has antibiotic resistance gene
C. Whose origin supports high copy number
D. Which has only one restriction site

Answer 1

Hint: Recombinant DNA technology is the process of genetic engineering involving the incorporation of the genome of one organism into another to get the desired genome which is then used for the production of various required gene products.

Complete answer: Genetic engineering is the process in which DNA is manipulated to get the desired set of genes in the organism.
1. This technique used many enzymes like the restriction enzymes, ligases, and many others. 2. Vectors are plasmids that are used to insert the desired DNA segment into the host genome.
3. They have specific restriction sites that are the same in the case of both the plasmid and the host genome.
4. The insert is made in the plasmid vector which is then transferred to the host genome.
5. This segment of plasmid DNA using the restriction enzymes first finds a suitable place for itself in the host genome to bind, (same sequence) and then is ligated.
6. The restriction enzymes can produce either sticky or blunt ends that bind to the desired segment of plasmid DNA to the host. Further, these replicate inside the host cells and produce many copies of the enzyme or protein for which the insert was given.
7. When many copies of the target DNA have to be recovered then the plasmid vector must have a high copy number which will enable it to produce more copies of the desired target gene inside the host cell.

So the correct answer is C. Whose origin supports high copy number

Note: The copy number of a plasmid varies from one plasmid to the other and this is something which is taken into consideration while the selection of the desired plasmid is done and further the genome of that plasmid is subjected to the process of genetic engineering.