Nondisjunction- A chromosomal mutation that produces an offspring with an incorrect number of chromosomes.

Recessive Genes- Expressed in an organism only in the absences of a dominant allele.

Dominant Genes- Always expressed in an organism.

Somatic Cell- A body cell.

Germ Cell- A reproductive cell.

Karyotype- A visual display of an individual's chromosomes, which are paired and numbered.

A genotype is you genes, and your phenotype is your physical features, so if a person has blue eyes another person can infer that the one with blue eyes has the genes to code for blue eyes.

Klinefelter's Syndrome- A genetic syndrome that causes the males to have an extra X chromosome. It comes from a germ cell. This disease is neither dominant or recessive.

Down Syndrome- An extra chromosome in the 21 chromosome. It's neither recessive or dominant. It comes from a germ cell.

Colorblindness- A reduced ability to be able to tell the difference between certain colors. Different types of this disease can either be recessive or dominant, so it could be either, depending on the type the person has. Color blindness comes from a germ cell.

Turner's Disease- A disease in which a female is only born with 1 X chromosome. It is a neither recessive or dominant because it's not genetic disease, but a chromosomal disease. It is from a germ cell.