The human body has 46 chromosomes and these chromosomes come in pairs, making 23 pairs in the body. When looking at the Karyotypes, or chromosomal profile of a person, these chromosomes are arranged in their pairs based on their size.
Not an actual representation of an xy chromosome
The last, and smallest, chromosome (Chromosome 23), otherwise known as the sex-chromosome, determines the gender of the organism. The remaining 22 chromosomes are called the autosomes and will make up everything else about an individual other than the gender. However, traits found specifically on the sex chromosome are called sex-linked chromosomes. These chromosomes differ depending on whether or not the child is male or female. Considering that the male is the deciding factor as to whether or not the child in male or female (as they have the XY sex chromosome while females only have an XX sex chromosome), they are more likely to express sex linked traits
Squares are used to represent males while circles represent females. A shaded in shape represents an affected individual.
Pedigree charts tracks one specific trait pattern through familial generations. Sometimes an organism is bred for specific traits. Cross breeding for a single selected trait is called a monohybrid while one bred for two specific traits is a dihybrid.