| A | B |
|---|
| genetics | study of ways hereditary information is passed from parents to offspring |
| Gregor Mendel | investigated inheritance in pea plants |
| P generation | 1st group crossed |
| F1 generation | offspring of parent generation |
| f2 generation | offspring of F1 |
| hybrid | offspring of two pure parents |
| dominant | a trait, that when present, expresses itself |
| recessive | a hidden trait (only expressed when two are present) |
| gene | carried by chromosomes; 2 needed to express a trait |
| chromosome | found in the nucleus; carries hereditary information |
| allele | different copies or forms of a gene controlling a trait |
| homozygous | alleles for the trait are the same |
| heterozygous | alleles are different |
| genotype | genetic make of an organism |
| phenotype | physical traits determined by the genotype |
| law of dominance | when an organism is hybrid |
| law of segregation | genes, which control individuals are separated from each other and recombined at fertilization |
| gene-chromosome theory | genes are in a definite order on chromosomes |
| law of probability | chance; several possible events that might happen will happen in equal numbers over a large number of trials |
| principle of independent assortment | genes are separated and distributed independently of one another |
| gene linkage | genes are the same chromosome that are close together will not likely separate |
| crossing over | parts of chromosomes exchange segments - linked genes will move together |
| intermediate inheritance | traits in which there is no clear dominance |
| codominance | when heterozygous, both expressions of the trait are shown |
| incomplete dominance | when heterozygous, a new expression of the trait is shown |
| XX | female |
| XY | male |
| autosomes | any chromosomes that are not sex chromosomes |
| sex chromosomes | chromosomes that determine gender |
| pedigree | diagrams that show the presence or absence of a particular trait in each member of each generation |
| selection | choosing an organism with the most desirable traits for mating |
| inbreeding | mating closely related individuals; domesitication |
| hybridization(outbreeding) | mating two individuals not closely related |
