genotype
genetic constitution of an organism
phenotype
physical characteristic due to its genotype and its environment
dominant allele
always expressed in the phenotype
recessive allele
only expressed in the phenotype if 2 are present
codominant alleles
equally expressed in the phenotype
homologous chromosomes
a pair of chromosomes, one maternal and one paternal, that have the same gene loci
multiple alleles
a gene that had more than 2 allelic forms