NEET 2005 · Class 12

Principles of Inheritance and Variation

A woman with 47 chromosomes due to three copies of chromosome 21 is characterized by

  1. (A)superfemaleness
  2. (B)triploidy
  3. (C)Turner's syndrome
  4. (D)Down's syndrome

The NCERT line that answers it

Verbatim line

Down's syndrome results in the gain of extra copy of chromosome 21.

Chapter
Principles of Inheritance and Variation
Section
4.8.3 Chromosomal Disorders

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 directly states that Down's syndrome results from an extra copy of chromosome 21, which matches the question's description of a woman with 47 chromosomes due to three copies of chromosome 21.

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