NEET 2001 · Class 12

Molecular Basis of Inheritance

Sickle cell anaemia is induced due to

  1. (A)change of amino acid in a-chain of haemoglobin
  2. (B)change of amino acid in b-chain of haemoglobin
  3. (C)change of amino acid in both a and b chains of haemoglobin
  4. (D)change of amino acid either a or b chains of haemoglobin

The NCERT line that answers it

Verbatim line

A classical example of point mutation is a change of single base pair in the gene for beta globin chain that results in the change of amino acid residue glutamate to valine.

Chapter
Molecular Basis of Inheritance
Section
5.6.1 Mutations and Genetic Code
Page
18
Words matched
43 of 43

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

How this line gives the answer

3333, emb=0.7672, combined=0.5937). Verified: high — The span explicitly states that sickle cell anemia results from a point mutation in the gene for the beta globin chain, which directly corresponds to the β-chain of hemoglobin, making option B conclusively correct.

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