AP BIOLOGY

Detailed explanation-1: -Two of the chromosomes (the X and the Y chromosome) determine your sex as male or female when you are born. They are called sex chromosomes: Females have 2 X chromosomes. Males have 1 X and 1 Y chromosome.

Detailed explanation-2: -Each person normally has one pair of sex chromosomes in each cell. The Y chromosome is present in males, who have one X and one Y chromosome, while females have two X chromosomes. Identifying genes on each chromosome is an active area of genetic research.

Detailed explanation-3: -The X chromosome is about three times larger than the Y chromosome, containing about 900 genes, while the Y chromosome has about 55 genes. Female mammals have two X chromosomes in every cell. However, one of the X chromosomes is inactivated.

Detailed explanation-4: -Boys typically have one X chromosome and one Y chromosome, or XY, but boys with XYY syndrome have an extra Y chromosome, or XYY. XYY syndrome is not caused by anything the parents did or did not do. The disorder is a random error in cell division.