What is a dominant trait?

A dominant trait is one that is expressed in the phenotype even when only one allele is present, meaning that it can overshadow the effect of a recessive allele. When an organism has a dominant allele paired with a recessive allele for a specific trait, the dominant allele will determine the observable characteristic. This principle is a fundamental concept in genetics that arises from Mendelian inheritance.

For example, if the allele for purple flowers (dominant) is paired with the allele for white flowers (recessive), the flowers will appear purple because the dominant trait is expressed. This highlights the importance of allele interaction in determining traits that are visible or recognizable in an organism.