Download App

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 Escherichia coli, lac operon is induced by
  • ✓
    $lactose$
  • B
    $promotor\; gene$
  • C
    $b-galactosidase$
  • D
    $I-gene$
✓

Answer

Correct option: A.
$lactose$
a
The inducer for Lac operon of Escherichia coli is lactose (actually allolactose or metabolite of Lactose). This lac operon normally remains inactive. When lac operon contacts with lactose, the lactose acts as an inducer and combines with the repressor, and the repressor is detached from operator gene. Thus $RNA$ - repressor, and the repressor is detached from operator gertural genes and polymerase enzyme gets its passage and reaches to the structural starts the transcription.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from STD 12 - 5. molecular basis of inheritance→STD 12 - 5. molecular basis of inheritance — all question types→Biology STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

Pollinator mutualism are special interactions involving ...$A$..., which receive food or a place to lay eggs and ...$B$..., which receive polle from other of their kind.

Choose of correct option for $A$ and $B$

→
Withdrawal of which of the following hormones is the immediate cause of menstruation?
→
Members of which plant family, pollen grains maintain viability for months ?
→
Latest trend in plant disease control is
→
Which of the following is a sexually transmitted disease?
→
Which enzymes fragment DNA?
→
Plants, bacteria, fungi and animals whose genes have been changed by manipulation are called
→
Vegetative propagation by $...........$ occurs in sweet potato.
→
MTP..
→
Mycorrhiza is responsible for the nutrition of which element?
→