XY

Cell Biology, Basic Genetics, Gender Science. Human cells contain 23 pairs of chromosomes for a total of 46. There are 22 pairs of autosomes and one pair of sex chromosomes. Chromosomes determine everything from hair color and eye color to gender. Whether you are a male or female depends on the presence or absence of certain chromosomes.The sex chromosomes are the X chromosome and the Y chromosome. These chromosomes determine gender. In human sexual reproduction, two distinct gametes fuse to form a zygote. The male gametes or sperm cells in humans and other mammals are heterogametic and contain one of two types of sex chromosomes. They are either X or Y. The female gametes or eggs however, contain only the X sex chromosome and are homogametic. The sperm cell determines the sex of an individual in this case. If a sperm cell containing an X chromosome fertilizes an egg, the resulting zygote will be XX or female. If the sperm cell contains a Y chromosome, then the resulting zygote will be XY or male.