DNA Replication is carried out by a complex system of enzymes.

DNA replication is carried out by a complex system of enzymes.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

DNA replication is carried out by a complex system of enzymes.

DNA replication is carried out by a complex system of enzymes.

DNA replication is carried out by a complex system of enzymes.

DNA replication is carried out by a complex system of enzymes.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

DNA Polymerase can only add nucleotides to the 3’ end of a primer.

There were originally three separate theories of how DNA Replication could have occurred. Meselson and Stahl eventually proved that DNA Replication was replicated semi conservatively, through their famous experiment involving E. coli. As many generations of E.coli are allowed to replicate, the DNA they contain is composed of more N14 than N15. This shows up as a different band in the test tube, due to the heavier weight of the N15 as compared with N14.

Your task – To use a skit to explain the role of the enzymes in DNA Replication You must create a skit to explain the basics of the process of DNA Replication Your Skit must include the following: DNA Helicase RNA Primase DNA Polymerase III DNA Polymerase I DNA Ligase All enzymes must be labeled and the process must result in the formation of two strands of DNA produced semi-conservatively. DNA should be should be shown starting as a single double-stranded molecule, and turn into two double-stranded molecules. +

Sanger Sequencing – a method of determining the exact sequence of DNA in an organism. Dideoxynucleotides result in the termination of a DNA sequence. Sanger used this to determine the sequence of DNA by the following: -DNA Replication is performed on a sequence of choice many times times using Dideoxynucleotides. (One set for A,T,G,C) -This revealed the last base in each of the sequences. -Then the sequences are overlaid on top of one another, and you can see each of the bases in a specific set of nucleotides. Check out this animation to see the process in action.

Short Tandem Repeats (STRs) are short sequences of DNA contained in the highly repetitive sequences that differ greatly between individuals. Since there is a high amount of variance between these sequences in individuals, they can be used with relatively high efficacy to match suspect DNA to samples found at a crime scene. Comparisons of the lengths of these STRs are useful in DNA Profiling. See if you can see the differences between Bob and Anne’s STRs in the diagram to the right.