A person who is trisomic for chromosome 18th pair is :

A person who is trisomic for twenty first pair of chromosomes is or Number of sex chromosomes is normal in

The person who first described polytene chromosomes was :-

Assertion : Trisomic condition of chromosome 13 result in Down's syndrome Reason : It is characterized by sever mental retardation.

(A): Trisomic condition of chromosome-21 results in Down's syndrome Reason (R): Mitotic or meiotic non-disjunction of sex chromosomes causes autosomal abnormalities.

If haploid chromosome number in an organism is12, what is the chromosome number present in its trisomic ?

State whether the following statements are true or false Down's syndrome is caused by the trisomy of the 10 th pair of chromosome.

A trisomic indidual possesses extra -chromosomes :

On analysis , a person 's karyotype reveals an extra one chromosome of twenty first pair . What does ths condition represents ? Which type of symptoms can be noticed in the person ?