On pg 176 of Your Inner Fish, Shubin describes the developement of clowns from humorless couples. He attributes the developement of the family full of clowns to mutation. However, a family full of clowns can develope regardless of the mutations. Describe the developement of the Bonzo family from the hereditary aspects from the humorless couple all the way to a full fledged clowns.
Kevin Jeon:bboybyung@gmail.com
As described on page 176-177, the Bozo family turned into a full family of clowns once all the aspects were covered. In other words, when the offspring had a squeaky nose, floppy feet, and curly hair, then the full-fledged family of complete clowns would be made. Step by step, mutilations occurred because of one of multiple reasons. There could have been a point mutation where a certain nucleotide was changed, and in response, an abnormal protein was created. There could have been a missense mutation where one a wrong amino acid is added in place of the right amino acid in a protein chain. There could have been a nonsense mutation in which the translation of mRNA is “terminated prematurely”. There could also have been a frame shift mutation which is the addition of a nucleotide and its pair which completely shifts the translation sequence. It can lead to the wrong amino acids being added in the chain. Last but not least, there could have been a missing amino acid which can cause a completely different protein because a change in shape leads to a change in function of the protein (Campbell 344-345). Any of these types of mutations can lead to the change in features from the first generation of the Bozo family. Because of these mutations, the second generation consisted of an offspring with a squeaky nose. These mutations also cause the third generation to have floppy feet. And consequently, these mutations cause the 4th generation to have curly hair. Once the 4th generation was created, it could have also had a mutation in the genes that led to the creation of abnormal round red lips. However, no mutations occurred in Shubin’s example, thus the next generation was the same as the previous generation.
ReplyDeleteSources:
Campbell (Chapter 17)
Shubin
Shreeraj Patel
shreeraj.patel1@gmail.com
I agree 100% with Shreeraj on how these genetic mutations may have arisen. As stated by Campbell, mutations are responsible for the great diversity in the human genome, and why there is such variation as evolution took place over millions of years. Without mutation, there would be no variation or evolution, and without evolution, humans wouldn't exist. The process of mutation is directly linked to the biological theme of structure and function. The mutation of genes during the process of DNA translation can alter the sequence of the DNA code, which can lead to different proteins being made by the DNA that can either help or harm a cell. Examples of these are hereditary diseases which are caused by point mutations and can be passed down to offspring, or selective advantages that promote success for a species in the future. When the structures of the proteins are altered, they become an entirely different protein, which changes the function of the protein to another job. This change may have a positive or negative impact, depending upon the proteins former and new functions.
ReplyDeleteAlthough I agree with Shreeraj on his description of different types of mutations, I respectfully disagree somewhat on his statements about the clown example presented by Shubin. I will agree that mutations caused the different features. However, the mutations from the previous generation did not cause more mutations, but rather they simply caused a new physical feature to appear in the clown family. Instead, the old mutated genes were passed down from each generation, causing the features to continue to reappear. With each new mutation per generation, genes were altered that caused proteins to switch structure and therefore function, resulting in floppy feet or squeaky noses. These are all examples of how mutation would occur, which is why I would disagree with the statement that Shreeraj made that no mutations occurred in this example given by Neil Shubin. These mutations and this example actually detail a very relevant idea in modern biology: that these mutations can help us trace lineages by biological features that arose from generation to generation. This directly relates to the biological theme of evolution, in that mutation provides for genetic variation and diverse genomes, which is why in modern society, there are such large differences between different populations of humans around the world. Through genetic mutation, so much variation occurred that humans have evolved from previous species to what we are today. Therefore, this bozo family tree helps illustrate to us a very simple idea; that mutations have occurred all throughout evolutionary history, which is why we see such changes as an unclown couple to a fully fledged clown family, or how homo sapiens diverged from the more general homo genus millions of years ago, all the the way up until now.
Sources:
Campbell P.344-346
Your Inner Fish: P.175-178
Matt Kim
(matthewkim0803@gmail.com)