Idea or model
Dominant and recessive
A dominant allele shows its effect with one copy; a recessive allele shows its effect only with two copies.
One of two or more versions of a DNA sequence at the same place in the genome. You inherit one from each parent.Source: NHGRI
Idea or model
A dominant allele shows its effect with one copy; a recessive allele shows its effect only with two copies.
Idea or model
Mendel's pea crosses showed that traits are inherited as separate units, giving predictable ratios such as 3 to 1.
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
National Human Genome Research Institute. Talking Glossary of Genomic and Genetic Terms. National Human Genome Research Institute, NIH.