Chromosomal disorders are genetic conditions caused by abnormalities in the number or structure of chromosomes. Humans typically have 46 chromosomes, arranged in 23 pairs. When there is an extra chromosome, a missing chromosome, or a structural change, it can lead to various health issues and developmental challenges. Common examples of chromosomal disorders include Down syndrome, which is caused by an extra copy of chromosome 21, and Turner syndrome, resulting from a missing or incomplete X chromosome in females. These disorders can affect physical growth, cognitive abilities, and overall health, requiring tailored medical care and support.