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Dna And Sequence Of Dna Essay

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DNA (deoxyribonucleic acid) is a self-replicating nucleic acid that carries the genetic information in cells in a double helix structure. The 2 stranded helix is composed of 4 nucleotides, Adenine (A), Thymine (T), Guanine (G), and Cytosine (C). The base pairs only form between A and T connected by 2 Hydrogen bonds and G and C connected by 3 hydrogen bonds. Foremost DNA wrapping comes about as DNA wraps around protein called histones. These combined loops of DNA and protein are called nucleosomes and the nucleosomes are packaged into a thread called chromatin. Chromosomes are made up of packaged chromatin and can be seen in the nucleus of dividing cells and form around DNA replication. Furthermore, DNA replication begins with 2 DNA strands being separated by the helicase enzyme. Single stranded DNA binding proteins attach to these strands to keep them from re-connecting. 1 DNA strand begins to encode called the leading strand, which Forms from 5’ to 3’ end using DNA polymerase 3 the primary polymerase. The other strand is referred to as the lagging strand, which presents problems because it has to form from the 5’ to 3’end as well. As continuous replication of the leading strand continues the lagging strand forms in pieces called Okazaki fragments. RNA primase forms as RNA primer and polymerase III lay down new DNA. This process repeats again and again. DNA polymerase I replaces RNA primers with DNA and DNA ligase links the Okazaki fragments. Along with the process of DNA

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