A DNA molecule is made up of a sugar backbone and four flavors of a molecule called al
These
nucleotides are arranged along the backbone in a unique
order. Moving up a level of organization, we have
Lare passed on from parents to
children in the form of genes. The next level up is the
chromosome. Humans have Lof these, arranged in
pairs. Chromosomes contain many!
along
with long stretches of DNA
tes