Howard Hughes Medical Institute
Understanding Variation
Does where we live influence how our bodies express genetic traits? Explore variation in human skin color with an activity that incorporate video and hands-on learning. Individuals model the relationship between phenotypes and genotypes,...
Khan Academy
Khan Academy: Variations on Mendel's Laws (Overview)
Article reviews Mendel's basic model of inheritance then provides an overview of variations on Mendel's laws, including multiple alleles, incomplete dominance, co-dominance, pleiotropy, lethal alleles, sex linkage, genetic interactions,...
CK-12 Foundation
Ck 12: Biology: Natural Selection
[Free Registration/Login may be required to access all resource tools.] Describes how natural selection changes allele frequency.
CK-12 Foundation
Ck 12: Life Science: Polygenic Traits
[Free Registration/Login may be required to access all resource tools.] Another exception to Mendel's rules is polygenic inheritance, which occurs when a trait is controlled by more than one gene. This means that each dominant allele...
BiologyWise
Biology Wise: Dominant and Recessive Traits in Humans
Explains what dominant and recessive traits are and how they work, and provides a list of single gene traits with the degree of manifestation if they are dominant or recessive. Also discusses co-dominance, incomplete dominance, polygenic...