NEET 1995 · Class 12

Molecular Basis of Inheritance

An environmental agent, which triggers transcription from an operon, is a

  1. (A)depressor
  2. (B)controlling element
  3. (C)regulator
  4. (D)inducer

The NCERT line that answers it

Verbatim line

Lactose is the substrate for the enzyme beta-galactosidase and it regulates switching on and off of the operon.

Chapter
Molecular Basis of Inheritance
Section
5.8.1 The Lac operon
Page
22
Words matched
24 of 24

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states 'Lactose...regulates switching on and off of the operon. Hence, it is termed as inducer,' which directly defines an inducer as an environmental agent triggering transcription from an operon.

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