DNA and RNA
Thomas Hurley
11/18/2014
DNA & RNA
Deoxyribonucleic acid and ribonucleic acid also know as DNA and RNA a closely related molecules that participate in transmitting and expressing genetic information. Both the DNA and the RNA have molecular chains containing alternating units of sugar and phosphate. Now each sugar unit has nitrogen containing molecules called nucleotide bases that hand off of them. The different sugar units in DNA and RNA are responsible for the differences between the two biochemicals. To contrast DNA and RNA you need to look at the physical structure of the two. DNA and RNA are identical except that on carbon binds to a hydrogen atom instead of a hydroxyl group. This difference means that two strands of DNA can form a double-helix structure while the RNA remains as a single strand. With that being said DNA 's double-helix structure is very stable, giving it the ability to encode information for a long time. Moreover, the cell creates RNA as needed during the process of transcription, but DNA is self-replicating.
Now for human evolution regarding one central repository of DNA. I like to think of this question like this: If you cut yourself and your skin cells had to call down to the central repository for instructions on how to make new skin cells, you would never heal. Each cell has its own DNA, which has the blueprint for what that cell is and what it does as a function for that part of the body. The DNA is housed in the cells nucleus, located in a central part of the cell. Think of the DNA and the nucleus as being the "thinking part" of the cell; it tells the cell what to do, how to do, and when to do. It is a very active part of the cell 's life cycle, so much so that necessity dictated it be located on site within the cell. Things evolve, often times, out of necessity, so the need to have the DNA, which is different for each type of cell, "local" as opposed to "long distance", seemed to be the path of least resistance.
11/18/2014
DNA & RNA
Deoxyribonucleic acid and ribonucleic acid also know as DNA and RNA a closely related molecules that participate in transmitting and expressing genetic information. Both the DNA and the RNA have molecular chains containing alternating units of sugar and phosphate. Now each sugar unit has nitrogen containing molecules called nucleotide bases that hand off of them. The different sugar units in DNA and RNA are responsible for the differences between the two biochemicals. To contrast DNA and RNA you need to look at the physical structure of the two. DNA and RNA are identical except that on carbon binds to a hydrogen atom instead of a hydroxyl group. This difference means that two strands of DNA can form a double-helix structure while the RNA remains as a single strand. With that being said DNA 's double-helix structure is very stable, giving it the ability to encode information for a long time. Moreover, the cell creates RNA as needed during the process of transcription, but DNA is self-replicating.
Now for human evolution regarding one central repository of DNA. I like to think of this question like this: If you cut yourself and your skin cells had to call down to the central repository for instructions on how to make new skin cells, you would never heal. Each cell has its own DNA, which has the blueprint for what that cell is and what it does as a function for that part of the body. The DNA is housed in the cells nucleus, located in a central part of the cell. Think of the DNA and the nucleus as being the "thinking part" of the cell; it tells the cell what to do, how to do, and when to do. It is a very active part of the cell 's life cycle, so much so that necessity dictated it be located on site within the cell. Things evolve, often times, out of necessity, so the need to have the DNA, which is different for each type of cell, "local" as opposed to "long distance", seemed to be the path of least resistance.
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