Question

If a person obtains transformants by inserting a recombinant $DNA$ within the coding sequence of enzyme $\beta$-galactosidase, he will separate out recombinants from non-recombinants by which of the following observations?

• A. Non-recombinant colonies do not produce any colour whereas recombinants give blue coloured colonies
• B. Recombinant colonies do not produce any colour whereas non-recombinants give blue coloured colonies
• C. Recombinants and non-recombinants both produce blue coloured colonies
• D. No colonies are formed due to insertional inactivation

Answer 1

Answer: (B)

Correct answer is (b) Recombinant colonies do not produce any colour whereas non-recombinants give blue coloured colonies