| A | B |
|---|
| multiple alleles | Three or more forms of a gene that code for a single trait. |
| sex chromosomes | A pair of chromosomes carrying genes that determine whether a person is male or female. |
| 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, but does not have the trait. |
| genetic disorder | An abnormal condition that a person inherits through genes or chromosomes. |
| pedigree | A chart or "family tree" that tracks which members of a family have a particular trait. |
| karyotype | A picture of all the chromosomes in a cell arranged in pairs. |
| selective breeding | The process of selecting a few organisms with desired traits to serve as parents of the next generation. |
| inbreeding | A selective breeding method in which two individuals with identical or similar sets of alleles are crossed. |
| hybridization | A selective breeding method in which two genetically different individuals are crossed. |
| clone | An organism that is genetically identical to the organism from which it was produced. |
| genetic engineering | The transfer of a gene from the DNA of one organism into another organism, in order to produce an organism with desired traits. |
| gene therapy | The insertion of working copies of a gene into the cells of a person with a genetic disorder in an attempt to correct the disorder. |
| genome | All of the DNA in one cell of an organism. |
