NEET 2010 · Class 12

Molecular Basis of Inheritance

The lac operon consists of

  1. (A)four regulatory genes only
  2. (B)one regulatory gene and three structural genes
  3. (C)two regulatory genes and two structural genes
  4. (D)three regulatory genes and three structural genes

The NCERT line that answers it

Verbatim line

The *lac* operon consists of one regulatory gene (the *i* gene – here the term *i* does not refer to inducer, rather it is derived from the word inhibitor) and three structural genes (*z*, *y*, and *a*).

Chapter
Molecular Basis of Inheritance
Section
5.8.1 The Lac operon
Page
21
Words matched
36 of 36

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 'The lac operon consists of one regulatory gene... and three structural genes', which directly matches the correct answer option B.

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