Klinefelter syndrome, which becomes apparent at puberty when secondary sexual characteristics fail to develop, results from
A) nondisjunction of autosomal chromosomes.
B) nondisjunction of sex chromosomes.
C) disjunction of autosomal chromosomes.
D) disjunction of sex chromosomes.

Question

Quizplus · Accepted Answer

Klinefelter syndrome is caused by the presence of an extra X chromosome in males, resulting from nondisjunction of sex chromosomes during meiosis. This results in XXY genotype instead of the normal XY genotype.

Klinefelter Syndrome, Which Becomes Apparent at Puberty When Secondary Sexual