| A | B |
|---|
| Dominance | A gene interaction where one allele is dominant and one is recessive and the dominant allele is expressed (example Huntington's Disease) |
| Incomplete Dominance | One allele is not totally dominant over another and together they form a combined allele/trait (Like Four O'Clock flowers - red and white make pink) |
| Codominance | Both alleles are active - you see both traits (Example Roan cattle or Sickle Cell Anemia) |
| Polygenetic Traits | Traits controlled by several genes (examples: height, weight, skin color) |
| Sex-Linked Traits | Carried on the X chromosome (Examples: Hemophilia, Colorblindness, Baldness) |
| Sex-Influenced | Traits caused by a gene that is expressed differently in males and females |
| Autosome | all chromosomes except gametes |
| Gamete | Sperm cell or Egg cell carries half the genetic information and determines sex of offspring |
| Sex Chromosomes | Another name for a gamete - determines sex of offspring and carries sex-linked traits |
| Homozygous | Alleles are the same - can be dominant or recessive - examples - RR or rr |
| Heterozygous | Alleles are different - example - Rr |
| Phenotype | The expression of a trait - examples - tall, short, red, colorblind |
| Genotype | The allele letters that represent a trait - examples - TT, Tt, tt, |
| XX | female - the two alleles that make and offspring female |
| XY | male - the two alleles that make an offspring male |
| Dominant Trait | Represented by a capital letter - the trait rules over a recessive trait - can be TT or Tt |
| Recessive Trait | Represented by a little letter - a trait the must have BOTH little letters to be expressed - tt |
| Punnett Square | A box used to represent a genetic cross - parents on outsides and offspring inside squares |
