Question

An XXY or an XO person can occur when the female has______ producing an egg with two___ or no____ chromosomes. The male produces the normal sperm of X or Y.

Answer 1

An XXY or an XO person can occur when the female has nondisjunction, producing an egg with two X or no X chromosomes. 

When there is nondisjunction in meiosis division of the gamete, the X chromosome of the egg might fail to separate, resulting in an egg with XX chromosome and other egg without X chromosome. When XX egg fertilized, it will become XXY and when O egg fertilized it become XO.