what is key to recognition of a trait whose expression is determined by the effects of two or more genes, like human height? (hint: this is called polygenic inheritance) select one: the trait varies along a phenotypic continuum in the population a mating between a homozygous and a heterozygous individual produces more than the expected number of offspring expressing the dominant trait. all of the alleles of the gene for that trait are equally expressed pleiotropy occurs.