A heritable trait with two different forms (dominant and recessive) is known as A: an allele. B: a genotype. C: a phenotype. D: a gene.

A selective sweep refers to what? A: The replacement of pre-existing genetic variation by the variation surrounding a selected allele B: Natural selection that targets a particular--"selected"--allele C: An advanced cognitive capability observed in expanded human social networks D: Patterns of phenotypic variation associated with assortive mating

A unit of heredity with two or more different forms (usually dominant and recessive) is known as A: an allele. B: a genotype. C: a phenotype. D: a gene.

中国大学MOOC: 等位基因（allele）为同一物种中同一基因座（locus）上的基因，这个定义很严谨。

Which of the following will change as a population evolves? A: the frequency of reproduction among individuals B: the number of individuals with recessive phenotypes C: the size of a population D: the frequency of a particular allele

What information is provided by the Hardy-Weinberg calculations? A: it tells if there has been a change in the allele frequency of a population B: it tells if there has been changes to the phenotypes observed in a population C: it tells if an individual is fit for survival D: it tells if an individual is likely to undergo evolution