Question

Identify the desirable characteristics for a plasmid used in rDNA technology from the following
a) Ability to multiply and express outside the host in a bioreactor
b) A highly active promoter
c) A site at which replication can be initiated
d) One or more identifiable marker genes

e) One or more unique restriction sites

• A. a, c and e only
• B. b, c and e only
• C. a, c, d and e only
• D. b, c, d and e only

Answer 1

The correct option is D b, c, d and e only

• The plasmid is the small circular DNA. These are extrachromosomal DNA which can replicate individually.
• The plasmid is inserted with the desired gene and then introduced in the host cell.
• The characters which make plasmid suitable to be used in rDNA technology and genetic engineering techniques:
• There should be an active promoter site and the origin of replication site called an Ori site.
• This region will allow the plasmid to replicate in the host. There should be marker genes which can be used to identify the recombinants.
• To insert the desired gene, there should be the presence of restriction sites.

So the correct answer is option D.