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DNA Replications, Testing, and PCR

(1) DNA replication is a method of growth, repair, and recovery. Give me the highlights for a cell making nuclear copies and for cells dividing for reproductive purposes. Not too much detail, because this could get lengthy. I will ask for more depth if I feel you did not cover the topic enough.

(2) Ever notice how presumptive testing uses mainly protein markers while DNA testing does not? You know that DNA is the start and proteins are the result. Explain the role of RNA and give an example of how this supportive polymer could be used in the forensic field.

(3) The first topic this week discussed harnessing the machinery already in place naturally to use for our purposes. So, what is required for PCR and what components of the natural process of replication are we artificially mimicking? As an example, the primers we use in the reaction mimic the ability of the body to select which portion of DNA is replicated. What do the following mimic: Buffer, Taq polymerase. Magnesium. Add any other components you wish.

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(1) DNA replication is a method of growth, repair and recovery. Give me the highlights for a cell making nuclear copies and for cells dividing for reproductive purposes. Not too much detail, because this could get lengthy. I will ask for more depth if I feel you did not cover the topic enough.

DNA replication is the process of copying a complementary strand using the parent strand as the template. (1) DNA replication depends on the Watson-Crick base pairing rule, where each base in the template strand will determine the subsequent complementary new bases in the new strand. (1) DNA replication depends on the DNA polymerase enzyme that helps in adding bases to the new strand. (1) DNA replication typically begins at a fixed origin, and then continue bidirectionally at an open replication fork. (1) The initial step in DNA replication is the unwinding of DNA at the origin of replication by a protein called helicases. (1) The DNA polymerase cannot initiate or start the extension of the new complementary strand. (1) DNA replication must be initiated with a "short oligonucleotide forming a region of duplex DNA" called a primer. (1) Primer is needed to start DNA replication. (1) The synthesis of a new complementary strand by DNA polymerase only occurs in the 5' ---- 3' direction. (1) DNA synthesis by DNA polymerase moves in the 3'---- 5' direction on the template strand. (1) DNA synthesis generates a continuous new strand toward the replication fork called the leading strand, while synthesizing the other strand in a discontinuous fashion called the lagging strand. (1) The synthesis of the lagging strand moves away from the replication fork. (1) As mentioned before, there are proteins called DNA helicases that act to unwind the DNA double helix for the start of the DNA replication. (1) Helicases are really enzymes that break the hydrogen bonds that hold the two DNA strands together in a double helix. (1) The steps of DNA replication and synthesis happen in every cell that is dividing for ...

Solution Summary

The following posting answers questions regarding DNA replication, genetic testing and PCR testing.

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