Medical Definition of Chromosomes
Chromosomes: The microscopically visible carriers of the genetic material. They are composed of deoxyribonucleic acid (DNA) and proteins and, under a microscope, look like little rods.
Humans normally have 46 chromosomes -- 44 autosomes (nonsex chromosomes) plus XX sex chromosomes in the case of the female and XY sex chromosomes in the case of the male.
For a more thorough consideration of our chromosomes, please see the entry to Chromosome.
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