Biology 30 Genetics Practice Test

This question is about true breeding, which means the parents are genetically the same for a given trait. When two individuals that are genetically identical (homozygous) for that trait mate, their offspring inherit the same alleles and show the same phenotype generation after generation. That stable, uniform inheritance is what we call purebred. Crossing two true-breeding individuals for a trait results in offspring that are also true-breeding for that trait.

Hybrid would be offspring from genetically different parents and often show more variation due to heterozygosity. Codominant describes a pattern of allele expression, not the sameness of the parents. Non-Mendelian refers to inheritance patterns that don’t follow standard Mendelian laws.