Occasionally when children question why they are not measuring up to what they want to become, they then go to their parents for some answers. Some parents may not be knowledgeable in the fact that some of the answers reside in the dominant and recessive genes.
Mendel, during his study of plants realized that each plant contained two factors for a particular trait. In some plants the two factors (genes) were both for the tallness trait. These plants were true breeders and only produced tall plants. In a like-wise manner short plants contained two shortness factors were true breeding short plants. In instances when a plant contained both tallness and shortness factors, the plant would grow tall. This particular plant might still pass on on its shortness factor to the next generation of plants.
Today scientists use symbols to represent different forms of traits. The capital letter represents dominant genes and the small letter represents recessive genes.
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Shortness in the parent generation (P1) generation, disappears in the first generation (F1) generation, and reappears in the second generation. (F2 generation). What is true for the plant is also true of the animal for many traits.
Organisms that have genes that are alike for a particular trait (TT) are purebreds and organisms that have genes that are different for a trait (Tt) are hybrids.
In the case of incomplete dominance the genes are neither dominant nor recessive. The genes appear to blend together when they are inherited and become combinational. An example in animals for incomplete dominance is the Andalusian fowl. Neither black nor white feathers are dominant. When a gene for a black feathered fowl and a white feathered fowl is present, the fowl appears to have black feathers with tiny white dots.