The material covered in my genetics class helped me better understand the article, How Spiders Got their Knees, by Emily DeMarco. For example, the article describes how the Dachshund gene was duplicated and activated in the patella region which formed kneecaps, providing flexibility (DeMarco, 2015). In class I learned about the different types of errors that can occur during DNA replication and repair. I learned that duplication can occur through replication slippage or unequal crossing over. Also, three arrangements of duplications can occur, which are known as tandem, reverse tandem, and terminal tandem. The material discussed in class helped me visualize how the Dachshund gene was duplicated. In addition, the article mentions how they
…show more content…
Gene deactivation is essentially gene suppression, which is another topic I learned in class. Gene suppression is described as a second gene blocking the mutant phenotype of the second gene. Through suppression, the phenotypic ratio of progeny resulting from a cross between two heterozygotes is altered from a 9:3:3:1 ratio that is generally expected. The example of such a cross provided in class allowed me to understand how the researchers deactivated the gene and figured out that is was responsible for creating knee caps as the resulting offspring only had one leg segment. Furthermore, the article explains how accidentally duplicating genes is a mechanism by which evolution can occur. In class we discussed that bar eyes in Drosophila are the result of duplication of the 16 A region. If there was an advantage to having bar eyes, perhaps over time the bar-eyed flies could potentially become their own species. This relates to the article because they have some evidence of arachnids evolving kneecaps and retaining this advantageous trait through evolution. Essentially, genetics is the driving force for evolution because minor changes in the genetic code can give rise to new structures, functions, phenotypes, and eventually new
Gene deactivation is essentially gene suppression, which is another topic I learned in class. Gene suppression is described as a second gene blocking the mutant phenotype of the second gene. Through suppression, the phenotypic ratio of progeny resulting from a cross between two heterozygotes is altered from a 9:3:3:1 ratio that is generally expected. The example of such a cross provided in class allowed me to understand how the researchers deactivated the gene and figured out that is was responsible for creating knee caps as the resulting offspring only had one leg segment. Furthermore, the article explains how accidentally duplicating genes is a mechanism by which evolution can occur. In class we discussed that bar eyes in Drosophila are the result of duplication of the 16 A region. If there was an advantage to having bar eyes, perhaps over time the bar-eyed flies could potentially become their own species. This relates to the article because they have some evidence of arachnids evolving kneecaps and retaining this advantageous trait through evolution. Essentially, genetics is the driving force for evolution because minor changes in the genetic code can give rise to new structures, functions, phenotypes, and eventually new