Class 12th Biology 2017 Set1 Delhi Board Paper Solution
Question 13
During a medical investigation, an infant was found to possess an extra chromosome 21. Describe the symptoms the child is likely to develop later in the life.
Answer
Down's Syndrome, the cause of this genetic disorder is the presence of an additional copy of the chromosome 21. This disorder was first described by Langdom Down. The affected individual is short statured with small round head furrowed tounge and partialy open mouth. Palm is broad with characterstic palm crease. Physical psychomotor and mental development is retarted.
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