Here's a breakdown:
* Genes: Genes are units of heredity that determine specific traits. We inherit two copies of each gene, one from each parent.
* Alleles: Different versions of the same gene are called alleles.
* Dominant and Recessive Alleles: In some cases, one allele (the dominant allele) masks the effect of the other allele (the recessive allele). This is why you might have brown eyes even though you have an allele for blue eyes.
* Codominance: In codominance, both alleles are equally expressed. This means that both versions of the gene are visible in the individual's phenotype (observable characteristics).
Example of Codominance:
* Blood Type: The ABO blood group system is a classic example of codominance. There are three alleles: A, B, and O.
* A and B are codominant: If you inherit an A allele and a B allele, you will have AB blood type, expressing both A and B antigens on your red blood cells.
* O is recessive: If you inherit an O allele, it will only be expressed if you inherit another O allele.
Key Points:
* In codominance, both alleles are expressed equally, leading to a phenotype that shows traits from both alleles.
* Codominance is different from incomplete dominance, where the phenotype is a blend of the two alleles.
* Codominance is a type of inheritance pattern that leads to greater variation in phenotypes.
