Solution:
SOLUTION
The extranuclear small circular DNA in bacteria is known as a plasmid.
- Plasmids confer some unique phenotypic characters to bacteria such as resistance to antibiotics.
- Plasmids contain some genes known as selectable markers that can help in distinguishing transformants from non-transformants by selectively allowing the growth of transformants on a culture medium.
- For example, the gene coding for beta-galactosidase enzyme acts as a selectable marker in the screening of transformants and non-transformants by looking at the color of colonies.
