Genetic Disorders

A karyotype is the number and appearance of chromosomes in the nucleus of a eukaryotic cell. In a human cell, there are twenty-three pairs of chromosomes, or forty-six individual chromosomes. The twenty-third pair of chromosomes identifies the sex of the organism. Females have two X chromosomes and males have an X and Y chromosome. Can you tell the sex of the organism in the karyotype shown?

By studying the karyotype of an individual, geneticists can also determine if any chromosomal disorders exist. Disorders exist when extra chromosomes are in a pair, or when chromosomes are missing from a pair. Chromosomes that are shorter than they should be are also linked to disorders.