The Art of Codominance

Codominance . . . an agreement. A mutual understanding between two alleles that agree to show in the offspring. An example of codominance can be eye color. If say the eye color green and blue are both dominant, then one eye will be green and blue. In a Punnett square, a codominant combination of alleles are both capital letters, but they have to be different. Codominance is like peace between two countries. If say they both want a certain piece of land, then they will both agree to have some parts of the land similar to one country, and another piece of land similar to the other country.

Incomplete dominance . . . a disagreement. Both of the alleles want to show but they won't agree on a mutual understanding. Show, they have to blend. An example of incomplete can be flower color. If one flower is red and another is white, then you would think that the dominant allele can take over the recessive allele. However, maybe both the red and white color allele are both dominant and they just won't agree on which one will win. So, because of the laws of nature, the offspring must have a color. Therefore, the colors blend and the flower is pink. If say these alleles were codominant, then there would be spots of red and white. On the other hand, these two alleles couldn't agree on a color so they had to blend.

Incomplete dominance and Codominance are two fascinating features that everyone should all learn sometimes in their lives. With this knowledge we can try to figure out who we got our genes from and if they have an example of an irregular combination of alleles. Incomplete dominance and codominance are all the part of the mysteries of life, and we can observe them and learn more about genes and alleles.

The Interesting Field of Genetics

For the past two weeks, I have learned the interesting field of genetics. This subject is the science of heredity and shows us what is related to what. Many credit this field to Gregor Mendel. He was a monk who studied the cross breeding of pea plants. From then on, scientists have experimented in genetics to such a degree that in 1996 a sheep named Dolly was cloned in Scotland.

First, we learned that humans have 46 chromosomes in a cell. The only exception is 23 chromosomes for a sex cell. Once the two sex cells fertilize, they then combine to make the 46 cells. Another interesting feature we learned about genetics was the Punnet square. The Punnet square shows the mathematical probability of which alleles the child will inherit from each parent in a neat and simple box. We first learned how to use a mono-hybrid Punnet square, a pretty basic concept. There is only one allele that you have to multiply by. Then, comes the di-hybrid punnet square where gametes come into play. To me, gametes are similar to the distributive property, which is what I told several students in my class to help them understand it better. If say you are told to show the possible combination's of alleles through a punnet square. You are then given these alleles: GgBB and GGbb. To find the possible alleles that the child will have, you have to use "the distributive property" as I mentioned before.

Because of genetics, scientists would not be able to read many different types of cells and its genetic material. We would also not be able to find the different alleles that each cell possess. Clearly, the field of genetics has had a huge impact on our world today.