The genetic information in organisms is divided up into genes, which are separate areas of genetic code that the life form can read and translate into a useful product. In humans, for example, these genes are collected in packages called chromosomes. Normally, a person gets one set from his mother and one set from his father. Therefore, he has duplicate genes.
A person may have two identical genes on both chromosomes for a particular trait, or he may have two different genes. Each gene codes for a particular trait, such as blue or brown eye color. Some genes have a stronger effect on traits than others, and these are known as dominant genes. The genes that do not produce any effect on the organism are called recessive.
Complete dominance occurs when an organism has two different genes and only one has an effect on the phenotype. This means that you could not tell if the organism Air Jordan 14s has only one gene or has two of the same genes for that trait simply by looking at that trait. An example of complete dominance is brown and black fur color in gerbils. The gene for the brown color is dominant to the black allele. Therefore, a gerbil with one brown and one black allele will always have brown fur, and an owner will Air Jordan 7s not be able to tell the gerbil has a black allele unless it mates with another gerbil and produces some black offspring with two recessive black alleles.
Codominance is a term that describes a phenotype that incorporates the information in both genes. An example is human blood type, where the genes code for “O”, “A” Nike Air Foamposite One or “B”. “O” is Air Jordan 2 recessive, and only people with two “O” genes have an “O” phenotype. “A” and “B” are dominant. When combined with “O,” they take over and the person’s blood type is “A” or “B.”
Another situation occurs when “A” and “B” alleles are both inherited together. Then codominance is the result, and the person has an “AB” blood type, Air Jordan 12s expressing both the “A” and “B” antigens on the outside of red blood cells.
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