DNA Replication By: Lexi Zanaglio

ADouble Helix Strand

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Key:PhosphateSugar

ATGC

AdenineThymineGuanineCytosine

Splitting of the Double Helix A

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In the Origin of Replication, Helicase unzips the DNA strand.

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Key:PhosphateSugar

ATGC

AdenineThymineGuanineCytosine

=Helicase

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Polymerase III adds nucleotides to the existing strands. The leading strand is added continually, while the lagging strand is more complex. Polymerase III can only add nucleotides a certain way. The lagging strand goes the opposite way that it needs to go for polymerase III to add nucleotides.

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= Polymerase III

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Primase has to add RNA primer to the DNA strand so polymerase III can start synthesizing nucleotides.Then polymerase III makes nucleotides until it reaches the next section of RNA primer these are called Okazaki fragments.

Then polymerase I replaces the RNA with DNA.

Then ligase forms phosphodiester bonds.

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TTwo exact copies of DNA are created

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Mutations DNA replication can have problems along the way, is the process is messed up or goes wrong there will be a mutation on the gene, an organism can only have up to 3 mutations to continue living.

TelomeresIs the compound structure at the end of a chromosome within a eukaryotic cell.It keeps other chromosomes within the cell from attracting to each other.

Okazaki FragmentsOkazaki fragments are short DNA fragments that are formed on the lagging strand in DNA replication. Polymerase III makes nucleotides until it reaches the next section of RNA primer and they are called Okazaki fragments.

DNA Ligase DNA ligase joins the DNA strands together by forming a phosphodiester bond.

TelomeraseAn enzyme that adds nucleotides to the telomeres, especially in cancer cells. They are found at the end of eukaryotic chromosomes.

CancerIs a disease caused by abnormal cells, dividing uncontrollably in a part of the body. Cancer is one of the top 3 killers of Americans, and is a very serious disease.

Transplanted cellsIs when cells are taken from another person or place in your body and put into your or someone else's body. There are multiple different types of transplanted cells, like for example stem cells can be transplanted.

Cloninga cell or organism that is genetically identical to the individual from the specimen it was taken from.

Aging The process of someone growing older and eventually becoming elderly. This is a gradual change in an organism that leads to increased risk of weakness, disease, and death. It takes place in a cell, an organ, or the total organism over the entire adult life span of any living thing.