| A | B |
|---|
| Alleles | The different forms of a gene |
| carrier | A person who has one recessive allele for a trait and one dominant allele, but does not have the trait |
| cell | The basic unit of structure and function in living things |
| clone | An organism that is genetically identical to the organism from which it was produced |
| codominance | A condition in which neither of two alleles of a gene is dominant or recessive |
| DNA | Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring |
| Dominant allele | An allele whose trait always shows up in the organism when the allele is present |
| gene | A segment of DNA on a chromosome that codes for a specific trait. |
| genetic disorder | An abnormal condition that a person inherits through genes or chromosomes |
| 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 |
| genetics | The study of heredity |
| genotype | An organism's genetic makeup, or allele combinations |
| Heredity | The passing of traits from parents to offspring |
| Homozygous | having two identical alleles for a trait |
| inbreeding | A selective breeding method in which two individuals with identical or similar sets of alleles are crossed |
| karyotype | A picture of all the chromosomes in a cell arranged in pairs |
| meiosis | The process that occurs in sex cells(sperm and egg) by which the number of chromosomes is reduced by half |
| multiple alleles | Three or more forms of a gene that code for a single trait |
| pedigree | A chart or "family tree" that tracks which members of a family have a particular trait |
| phenotype | An organism's physical appearance, or visible traits |
| probability | The likelihood that a particular event will occur |
| Punnett square | A chart that shows all the possible combinations of alleles that can result from a genetic cross |
| Purebred | An organism that always produces offspring with the same form of a trait as the parent |
| Recessive allele | An allele that is masked when a dominant allele is present |
| Replication | The process by which a cell makes a copy of the DNA in its nucleus |
| Selective breeding | The process of selecting a few organisms with desired traits to serve as parents of the next generation |
| Sex-linked gene | A gene that is carried on the X or Y chromosome |
| trait | A characteristic that an organism can pass on to its offspring through its genes |
| Variation | Any difference between individuals of the same species |
| Codominance | A condition in which neither of two alleles of a gene is dominant or recessive |
| incomplete dominance | The sbility of two alleles to produce a heterozygous phenotype that is different from either homozygous phenotype |
