a medium-sized chromosome with one long and one short arm. The position of the centromere, which separates the p and q arms, is shown by the hatched area. This particular idiogram depicts the ...

Inversions may involve the centromere. Isochromosomes. These chromosomes have two identical arms. Instead of the usual one p and one q arm, isochromosomes have two p or two q arms. They're lacking ...

For instance, the telomeres on chromosome 1's short arm (1p) differed by more than six kilobases between its two parts, 1pM and 1pP — the maternal (M) and paternal (P) chromosomes, respectively.