vocabulary

• Factor


  A variation of a trait
• Gene


  Unit of inheritance and/or portion of DNA that determines a trait
• Allele


  Different versions/variations of a gene for the same trait
• Genotype


  Combination of alleles that an individual has
• Phenotype


  Variation of a trait that is expressed shown in a individual
• Dominant


  The allele that will be expressed when present in a genotype
• Recessive


  The allele that will only be expressed if no dominant allele is present in the genotype
• Homozygous


  A genotype in which the two alleles are the same (pure breeding) blend
• Heterozygous


  A genotype in which the two alleles are different
• Trait - a feature, characteristic, or quality that is passed down from parent to offspring
• X-linked inheritance - when recessive allele is found on the X chromosome and the condition is expressed in males only
• autosomal recessive - two recessive alleles must be present for the person to express the trait
• autosomal dominant - only one allele needs to be present for the expression of the trait
• incomplete dominance - both 1 and 2 are expressed as a blend or intermediate of the original variations, neither is dominant over the other
• co-dominance - when two alleles are equally dominant and are expressed in the phenotype
• multiple alleles - more than two alleles for a gene, can result in more than three phenotypes