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NEET BIOLOGYPrinciples of Inheritance and VariationEasy

Question

If a female individual is with small round head, furrowed tongue, partially open mouth and broad palm with characteristic palm crease. Also the physical, psychomotor and mental development is retarded. The karyotype analysis of such an individual will show :

A

47 chromosomes with XXY sex chromosomes

B

45 chromosomes with XO sex chromosomes

C

47 chromosomes with XYY sex chromosomes

D

Trisomy of chromosome 21

Step-by-Step Solution

The symptoms described (small round head, furrowed tongue, partially open mouth, broad palm with characteristic palm crease, and retarded development) are strictly characteristic of Down’s syndrome . This genetic disorder is caused by the presence of an additional copy of chromosome number 21 (aneuploidy), known as trisomy of 21 . Option 1 (47, XXY) refers to Klinefelter’s Syndrome and Option 2 (45, XO) refers to Turner’s Syndrome.

Exam Context & Concepts Covered

This question aligns with the NEET BIOLOGY syllabus, specifically targeting concepts from Principles of Inheritance and Variation. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

BIOLOGYPrinciples of Inheritance and Variationfemaleindividualfurrowedtonguepartially

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B.Addition of one X chromosome
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