Principles of Inheritance and Variation · Class 12 · CBSE · Science Biology
Which of the following conditions correctly describes the chromosomal aberration responsible for Down's syndrome?
Practice question from Principles of Inheritance and Variation (Class 12 · CBSE · Science Biology), with the correct answer and a step-by-step solution.
medium · MCQ · Q-4629DE
Which of the following conditions correctly describes the chromosomal aberration responsible for Down's syndrome?
- A.Monosomy of sex chromosomes (45, X)
- B.Trisomy of chromosome 21Correct answer
- C.Trisomy of sex chromosomes (47, XXY)
- D.Deletion of the short arm of chromosome 5
Solution
Down's syndrome is a chromosomal disorder caused by the presence of an extra copy of chromosome 21, known as trisomy 21.
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