| A | B |
|---|
| allele | an alternative form of a gene |
| codominance | condition in which both alleles for a gene are expressed when present |
| continous variation | trait is controlled by several genes and exhibits a variety of phenotypes |
| dihybrid cross | cross involving 2 pairs of contrasting traits |
| dominant | trait expressed when its allele is homo or heterozygous |
| F1 generation | the offspring from a cross of two varieties |
| F2 generation | offspring of the F1 generation |
| genetic disorder | harmful effect produced by mutation |
| genetics | study of heredity |
| genotype | genetic constitution of an organism as indicated by its set of alleles |
| hemoglobin | component of red blood cells that binds with and carries oxygen through the body |
| hemophelia | genetic disorder that impairs the blood's ability to clot and can cause excessive bleeding |
| heredity | transmission of genetic traits from parent to offspring |
| heterozygous | Tt |
| incomplete dominance | a trait is intermediate between 2 parents |
| law of independent assortment | pairs of genes separate independently of one another in meiosis |
| law of segregation | pairs of genes separate in meiosis and each gamete receives one gene of a pair |
| monohybrid cross | cross involving one pair of contrasting traits |
| multiple alleles | having more than two alleles for a genetic trait |
| mutation | chance in the DNA of a gene or chromosome |
| pedigree | family history of traits recorded over generations |
| P generation | plants that displayed only one form of a particular trait |
| phenotype | physical characteristics of an organism |
| phenylketonuria | genetic disorder in which an indevidual lacks an enzyme that converts the amino acid phenylalanine into the amino acid tyrosine |
| probability | the likelihood that a specific event will occur |
| Punnet Square | diagram used to predict the possible outcome of a cross |
| recessive | trait that is not expressed in F1 generation after crossing |
| self pollination | process by which a plant pollinates itself |
| sex linked trait | a trait that is determined by a gene found on the X chromosome |
| sickle cell anemia | condition caused by a mutant allele that produces a defective form of the protein hemoglobin |
| true-breeding | displaying only one form of a particular trait in offspring |
