NEET Previous Year Question
The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of:
Topic: NEET PYQ
Answer: D. Full step-by-step solution below.
- AInactivation of glycosidase enzyme in recombinant bacteria
- BNon-recombinant bacteria containing beta-galactosidase
- CInsertional inactivation of alpha-galactosidase in non-recombinant bacteria
- DInsertional inactivation of alpha-galactosidase in recombinant bacteria
Correct answer: D
Solution
(d) Bacteria add methyl groups to specific DNA sequences to protect their own DNA from being cut by their restriction endonucleases. The restriction enzymes destroy foreign DNA (such as bacteriophage DNA), while the methylated bacterial DNA remains safe.More Biotechnology: Principles & Processes PYQs
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