Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA is the material that holds genes. It is the building block of the human body.

Chromosomes also contain proteins that help DNA exist in the proper form.

Chromosomes and DNA

Humans typically have 23 pairs of chromosomes, or 46 chromosomes in total. Chromosomes are made up of long strands of DNA, which contain all the body's genes.