| A | B |
|---|
| multiple alleles | three or more forms of a gene that code for a single trait |
| sex-linked gene | a gene that is carried on the X or Y chromosome |
| carrier | a person who has one recessive allele for a trait and one dominant allele, but does not have the trait |
| pedigree | a chart or "family tree" that tracks which members of a family have a particular trait |
| genetic disorder | an abnormal condition that a person inherits through genes or chromosomes |
| karotype | a picture of all the chromosomes in a cell arranged in pairs |
| sex chromosomes | a pair of chromosomes carrying genes that determine whethter a person is male or female |
| Male chromosomes | XY |
| Female chromosomes | XX |
| Cyctic Fibrosis | a body that produces abnormally thick mucus in the lungs and intestines |
| Sickle-cell Disease | Red blood cells have an abnormal, sickle shape and cannot carry as much oxygen as normal cells |
| Hemophilia | a person's blood clots very slowly or not at all |
| Downs Syndrome | a person's cells have an extra copy of chromosome 21 |
