| Alleles | Different variations of the same gene trait represented as uppercase and lowercase letters; genotypes consist of two allele letters, one comes from mom and one from dad |
| Genotype | The gene variation an individual possesses for a particular trait |
| Phenotype | How the genotype is physically expressed; the physical appearance |
| Autosomal Recessive | Trait that will only appear in the phenotype if organism inherits two of them; covered up by the dominant gene |
| Autosomal Dominant | An allele that controls the phenotype regardless of what the other allele is |
| Heterozygous/Hybrid | Having two different alleles for a particular gene; not true breeding |
| Homozygous/Purebred | Having two identical alleles for a particular gene; true or pure breeding |
| Law of Segregation | Alleles separate during the formation of sex cell gametes |
| Hereditary | Heredity refers to the genetic heritage passed down by our biological parents. It's why we look like them! |
| Genetics | The study of heredity, which is the inheritance of traits and characteristics passed on to the next generation |
| Punnett Square | Predicts the outcome probability of genetic crosses |
| Dihybrid Cross | Two gene punnett square |
| How did Mendel figure out the possible gamete combinations written along the two axes of his dihybrid cross? | He “foiled” each parent’s genotype |
| Law of Independent Assortment | Genes can separate during the formation of sex cells gametes and do not have to be linked or inherited together |
| Can we have a heterozygous/hybrid allele for a recessive trait? | NO! |
| What fur color would the offspring have if a hybrid female Arctic Fox had pups with a purebred male? (Phenotypic Ratio) | 4 White: 0 Dark Grey |
| Arctic Foxes can be white or dark gray. A heterozygous white Arctic Fox has pups with a dark gray Arctic Fox. What will their pups look like? (Genotypic Ratio) | 0FF:2Ff:2ff |
| Snowy owls can be pure white or slightly spotted. Slightly spotted feathers are dominant over all white feathers. If a homozygous spotted female has chicks with an all white feathered male, what will their chicks look like? (Genotypic Ratio) | 0FF:4Ff:0ff |
| Phenotypic and genotypic ratio for AaBb x aabb (1 pair heterozygous and 1 homozygous) | 1:1:1:1 |
| Dominant trait identification from a pedigree | - Every affected individual has at least one affected parent
- The trait is manifested in at least one individual in every generation once the trait appears |
| Codominance | Both alleles are equally as dominant so both are expressed side by side at the same time in a third phenotype |
| Incomplete Dominance | When one allele is not completely dominant over another resulting in a third mixed phenotype |
| Multiple Alleles | Genes with more than two alleles resulting in more than just two phenotypes |
| Polygenic Traits | Traits controlled by two or more genes resulting in many phenotypes |
| Sex Chromosomes | The sex of an individual depends on the presence or absence of a Y chromosome. A male’s sex genotype is XY while a female’s is XX. |
| Autosomes | Every other chromosome in your body because there’s only one pair of sex chromosomes per individual |
| X-Linked Traits | Only located on the “X” sex chromosome |
| Carrier | A heterozygous individual carrying a hidden recessive trait who therefore remains unaffected by that trait |
| What is a common example of a carrier who is carrying a hidden recessive trait, who remains unaffected by that trait? | Color Blindness |
| An example of multiple alleles is... | An excellent example of multiple allele inheritance is human blood type. Blood type exists as four possible phenotypes: A, B, AB, & O. There are 3 alleles for the gene that determines blood type. |
