Traits, Genes, and Alleles

Gene: a piece of genetic information that directs a cell to make a certain protein

Locus: a specific position on a pair of homologous chromosomes

Allele: any alternative form of a gene at a specific locus on a chromosome

Homozygous: alleles are identical to each other

Heterozygous: alleles are different from each other

Dominant: allele is expressed with 1+ dominant allele - Uppercase

Recessive: allele is expressed with 2 recessive alleles - lowercase

Punnett square: a grid system for predicting possible genotypes of offspring

Genotype: gene types

Phenotype: expression of genotype

Non-mendelian genetics: patterns of inheritance that do not follow Mendel’s hypothesis

Codominance: when 2 alleles appear in the phenotype

Incomplete dominance: when neither allele is dominant, creates a “new“ phenotype that is a blend of both alleles