The Four Organic Macromolecules

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Of the four organic macromolecules deoxyribonucleic acid, or DNA, is a nucleic acid. DNA is a double-stranded molecule comprised of numerous nucleotides covalently bound together. Nucleotides contain a deoxyribose sugar, a phosphate group, and one of four nitrogenous bases. The four nitrogenous bases are adenine (A), thymine (T), guanine (G), and cytosine (C). To construct DNA’s double helix, hydrogen bonds form between two complementary nitrogenous bases. These bonds only form between adenine and thymine and between guanine and cytosine (“DNA”).
DNA contains the instructions on how to create and build an organism. A gene is a sequence of nucleotides that code for different proteins, depending on the order of the nucleotides. In this way, genes
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The cathode (top of the agarose gel) is negatively charged while the anode (bottom of the gel) is positively charged. DNA, which is negatively charged, moves through the gel because of its attraction to the anode. Smaller fragments of DNA are lighter and move through the gel easier than larger fragments, so the small pieces of DNA migrate farther down the gel. From top to bottom, the DNA separates from larger pieces to smaller pieces respectively. Over time, the pieces of DNA spread out and putting a dye on the gel enables the researcher to see the bands, which are the pieces of DNA. The pattern that is created is compared to other DNA (“Gel …show more content…
To get the best possible results, the researcher must explicitly record all variables and conditions in the experiment. Variables such as the temperature during amplification, the primer to DNA ratio have to be kept constant to ensure that the results are valid. Changes in the variables will affect the results of the gel electrophoresis, either in position or how visible the bands are.
To improve future experiments that use DNA fingerprinting, Soll suggests using more than one primer to generate a clear pattern on the agarose gel. He supports that using short tandem repeats will garner the best results, because short tandem repeats are spread throughout the genome and will therefore produce a sufficient amount of variability. Also, this method is effective when analyzing genetic similarities and relatedness.
The method of DNA fingerprinting involving short tandem repeats, polymerase chain reaction, and gel electrophoresis is used for analyzing the homology among fragments amplified by the same primers and there are conclusive results (Soll 343-346). A researcher can take samples from a sufficient amount of people, DNA fingerprint the samples, and compare the variability throughout the samples. By doing this, it is possible to correlate results with physical traits or

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