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STD 12 - 5. molecular basis of inheritance — Biology STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceBiologySTD 12 - 5. molecular basis of inheritance1 Mark
MCQ
In the lac operon, the structural genes are switched off when
  • ✓
    Repressor binds to operator
  • B
    Repressor binds to promotor
  • C
    Repressor binds to regular
  • D
    Repressor binds to inducer
✓

Answer

Correct option: A.
Repressor binds to operator
a
(a)A short sequence of $DNA$ where the repressor binds preventing $RNA$ polymerase from attaching to the promoter this is called on/off switch of transcription.

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