Post by Admin on Sept 4, 2023 15:15:35 GMT
One of my favorite things about the Biology I learned was Genetics. I geeked out and became so infatuated with it, that I have on several occasions had fruit flies at home. The fruit fly, or scientifically called Drosophila melanogaster, has been used for over 100 years to study Genetics. Other than Mendel's pea plant crosses, the fruit fly has been the most important species used to study genetics and apply what was learned to other living species, including humans.
Fruit flies can vary in many ways by both Genotype and Phenotype. Genotype is what's in the genes that you can or can't see where as Phentoype is the characteristic that are easily seen. For example, a fruit fly may carry the recessive gene for the white eyes, which is its genotype, but that same fruit fly may have the dominant red eyes (as seen in fruit flies in the wild or in your kitchen on your fruit). Fruit flies can have many different phenotypes, that again you can easily see, like different colored bodies, different colored eyes, even some are born with wings that are shriveled up and can't fly (called vistigial wings). An interesting fact is that most of the varying fruit flies come from the very diverse islands of Hawaii. On the North American continent, you'll get the wild type that all look the same and all have the dominant Gene red eyes - called the "Wild Type" flies.
Regardless of the living species, be it plants, fungi, animals or others. the Punnet square can be used to predict the future generation of the offspring if they cross (or mate). Keep in mind that dominant Genes are represented by a capital letter and recessive, non-dominant, genes are represented with a smaller case letter. For example, R might be the wild type dominant red eye and a little r may represent the white eyed recessive gene in flies.
Keep in mind if any species receives one of the dominant genes from one "parent" and the recessive gene from the other parent, then the dominant gene will "dominate" or show up in the visible Phenotype. Also when they speak of "Alleles" in Genetics, the word simply means a Gene.
Here's a 3 minute video on this type of basic Genetics using the Punnet Square for predicting. I've even had 6th grade Science students cross and predict the outcomes with simple Punnett square genetics. Keep in mind if any species receives one of the dominant genes from one "parent" and the recessive gene from the other parent, then the dominant gene will "dominate" or show up in the visible Phenotype.
Michael Piziak