Give out two classification of chromosomal abnormalities

Numerical chromosomal abnormalities - polyploidy (triploidy, tetraploidy) - aneuploidy (monosomy, trisomy) Structural chromosomal abnormalities - Balanced (the exchange or rearrangement of genetic material does not cause any missing or extragenetic information) - Unbalanced (the structural chromosomal changes cause missing or extra genetic information)