In this Three class lesson I learned the difference between codominance and incomplete dominance. Codominance is when two dominant traits are both present in offspring instead of one overriding the other. Because they are both dominant, they both appear. The reverse of this is incomplete dominance, when you have two dominant traits but instead of both being present, they combine. This is how flowers of the same species can have multiple color variations. This difference is very prevalent in nature and is an essential piece to fully understanding genetics.
The punnet square is useful for determining the probability of an organism having a certain trait. One of the many pros to using this system is that the probability is easy to calculate and the genetic equations involved are kept extremely simple. When Mendel discovered how to use a punnet square, he created laws that work with it. There are some l was that do not work with the punnet square. Codominance, multiple alleles, incomplete dominance, and polygenic characteristics. These traits of organisms do not follow the punnet square directly and are a major drawback for the system. They turn the simple system of the punnet square into a more complicated equation. Although these are a major drawback, the square is still useful for single allele traits.
In the movie The Island, the cloning shown is not realistic. We do not yet know how to copy a persons DNA so that we can make another being exactly like it and this is the main premises of the movie. The retina scanner outside of a building is fictional as well. Retina scanners are unfortunately not found on every street corner in even our most advanced cities. The growth of the clones while in the "womb" is unrealistic as people do not grow to full size inside of their mother.
The video on the lesson 4 page shows how genetics started with Mendel. Without his discoveries using his pea plants, our understanding of genetics could be different. He examined the traits in his peas using a punnet square. He also used a much larger square to show the probability of a trait appearing out of the many different types of traits. Although the square was bigger, the ratio of four to one kept true in the second generation using the lar
Mendel made his hypotheses without any knowledge of DNA whatsoever. His two laws he discovered each can be proven without DNA or a microscope or both. This shows how great of a scientist Mendel was. He probably understood that something took the form of a genetic material but did not know that DNA was it. He also uses fairly obvious observations to support his claims opposed to very specific observations one can make when looking at the DNA of a creature. He based his work off of characteristics, not genetic material. Although he is sometimes called the father of genetics, he
In this three class lesson, I learned that cell division happens in many different ways. One of these ways is meiosis, or the creation of sex cells in more complex organisms. Another is a very simple kind of replication, binary fission. This type of replication occurs in single celled prokaryotes. All cell division happens to further continue a particular species. Although there are many types of cell division, they each serve a specific function that they are effective at.
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AuthorMichael Tellini Archives
May 2014
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