RNA

 RNA Wayne Xuan Block:E RNA is one of the most important structures in the human body. RNA is a long chain of nucleotide units. Each nucleotide consists of a nitrogenous base, a ribose sugar and a phosphate. It is shown as Pic1. And there are four types of nitrogenous bases –Adenine, Cytosine, Guanine, and Uracil. So there are four types of nucleotides and they arrange randomly to form all the different types RNA in the creatures. And their arrangement is shown as Pic2. Adenine can just combine with Uracil; Guanine can just combine with Cytosine. RNA is made in the crayons and DNA is used as the model. First, the DNA Helicase unwinds the DNA. And the dissociated nitrogenous bases will try to combine with DNA’s nitrogenous bases randomly. If two of the nitrogenous bases are matched, the RNA polymerase will combine the dissociated nitrogenous bases into a line. And that’s RNA. This process is called **//transcription//**. There are several types of RNA in our bodies-mRNA, tRNA, rRNA, snRNAs and others no-coding RNAs. RNA affects us so much, because RNA directs our cell to make the protein. The process of creating protein is very similar to the process which products RNA. First, the mRNA is used as a model. Second, the tRNAs will carry the Amino Acid to the mRNA. If the nitrogenous bases on tRNA (shown as Pic3) which just have 3 nitrogenous bases for each is matched with the nitrogenous bases on the mRNA, and then the ribosome will combine the Amino Acid together. And that’s the protein we need for constructing our bodies. There is one very interesting thing about the RNA. Although RNA is so useful and important in our bodies, it also helps some kind of virus to damage our bodies. Like HIV, its RNA can do the **// reverse transcription //** which means it can changes the RNA back into DNA. And it will add this extra DNA into our own DNA, so next time when DNA copy itself or produce the RNA. This extra part is in it and when the RNA product the protein, it will product the HIV virus. Then the new HIV virus will attack another cell and do the same thing again until all the cells contain the DNA of HIV.

Bibliography http://www.google.ca http://en.wikipedia.org/wiki/RNA http://en.wikipedia.org/wiki/HIV