The U.S. Constitutionâs 10th Amendment is arguably the most important of all the amendments in the brilliant document that helped shape the United States.
Not even identical twins have the same DNA--although theirs would be far closer than anyone else's. DNA changes over time. Odds of two siblings having the same DNA who did not split from the same zygote are vanishingly small.
Each person has DNA in the form of 23 pairs of chromosomes. One chromosome of each pair is inherited from our mother, and the other chromosome of each pair is inherited from our father. Unlike most of the cells in our bodies, the sex cells (sperm and egg) only contain a single copy of each of the 23 chromosomes.