Recessive alleles are the genes that do not show the trait. If a person carries two copies of the brown eye allele, since they are codominant, the person would have brown eyes. For example, if the dominant trait is red for flowers and another dominant trait is white, then the flower will have both red and white as the dominant traits are expressed equally. When you have two copies of the alleles that are both dominant, this is called codominance. You would need at least one copy of the brown eye allele (B) to have brown eyes. For example, the brown eye allele is dominant, B. If a person carries a heterozygous set of alleles (both uppercase and lower case letter of the gene) then the person will show the dominant trait (being that there is an uppercase letter present). With that being said, there are 2 sets of alleles that can be dominant or recessive. Remember that human cells carry 2 copies of each chromosome, one from the biological motherвЂ™s genes and one from the biological fatherвЂ™s genes. In order for a person to show the dominant trait, one of the personвЂ™s parents must have the dominant trait (which is an uppercase letter). Recessive alleles are seen as a lower case of a letter b. Alleles can be considered dominant or recessive, with dominant being the trait that is observed or shown and recessive being the trait is not seen.Дominant alleles are seen as an uppercase of a letter for example, B.

Different versions of a gene are called alleles.

Have you ever wondered why some people have blue or brown eyes? The coloring of the blue and brown eyes is an example of different versions of a gene. Understand why dominance sometimes doesnвЂ™t matter for sex-linked genes Know what it means for a gene to be dominant

Dominant traits and recessive traits