| A | B |
|---|
| Heredity | The passing on of characteristics from parents to offspring. |
| Genetics | The branch of biology that studies heredity. |
| Traits | Characteristics that are inherited. |
| Gametes | Another name for sex cells. |
| Fertilization | The uniting of male and female gametes. |
| Dominant | The trait that is observed, opposite of recessive. |
| Recessive | The trait that seems to "disappear". |
| Law of Segregation | Mendel's conclusion that a parent passes on one allele for each trait to its offspring. |
| Phenotype | The way an organism looks. |
| Genotype | The gene combination of an organism, type of genes. |
| Homozygous | Two alleles for the trait are the same, RR. |
| Heterozygous | Two alleles for the trait are different, Rr. |
| Dihybrid cross | A cross with two traits. |
| Monohybrid cross | A cross with one trait. |
| F1 | The first generation. |
| Rr x Rr | 3:1 ratio |
| RrTt x RrTt | 9:3:3:1 ratio |
| Rr x rr | 1:1 ratio |
| Homozygous red, homozygous tall | RRTT |
| Homozygous short | tt |
| Law of Independent assortment | Mendel's law stating that a random distribution of alleles occurs during the formation of gametes. |
| allele | alternative form that a single gene may have for a particular trait. |
| crossing over | exchange of chrosmosomal segments between a pair of homologous chromosomes |
| gene | functional unit that controls inherited trait expression |
| haploid | cell with half the number of chromosomes as a diploid cell |
| homologous chromosome | one of two paired chromosomes, one from each parent, that carries genes for a specific trait at the same location. |
| meiosis | reduction division process, occuring only in reproductive cells |
| genotype | an organism's allele pairs |
| hybrid | organism heterzygous for a specific trait |
| phenotype | observable characteristic that is expressed as a result of an allele pair. |
| Genetic recombination | new combination of genes produced by crossing over and independent assortment. |
| polyploidy | having one or more extra sets of all chromosomes which can result in greater size and better growth |
| centromere | what structure on the chromosome is reponsible for holding together the sister chromatids |
| gene | a segment of DNA that code for a particular trait |
| prefix "homo" | same |
| gene | anther term for chromosome |
