Chromosomes

Chromosomes are threadlike structures made of protein and a single molecule of DNA that serve to carry the genomic information from cell to cell. In plants and animals (including humans), chromosomes reside in the nucleus of cells. Humans have 22 pairs of numbered chromosomes (autosomes) and one pair of sex chromosomes (XX or XY), for a total of 46. Each pair contains two chromosomes, one coming from each parent, which means that children inherit half of their chromosomes from their mother and half from their father. Chromosomes can be seen through a microscope when the nucleus dissolves during cell division. Some intersex people can have a special variation that result in extra sex chromosome, such as XXX, or XXY, these are Jacobs Syndrome (XYY Syndrome or 47XYY) and Trisomy X (Triple XXX Syndrome).

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