X and Y chromosomes
X and Y chromosomes, or sex chromosomes, cell nuclei that determine the sex of a person (as well as carrying some genetic information not related to sex determination). Sex chromosomes are inherited in the same way as the other 22 human chromosome pairs, normal persons being either XX (female) or XY (male). The Y chromosome carries little genetic information, and it is largely the properties of the X chromosome that determine sex-linked characteristics in males. Sex-linked characteristics include hemophilia and color blindness, which are carried as recessive genes in females.
See also: Chromosome.