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Dna Structure

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Submitted By afitchgirl29
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University of Phoenix BIO/240 - GENERAL BIOLOGY Michael Shunk

Deoxyribonucleic acid or DNA is found in basically all organisms including humans. It is the hereditary material that basically every person has and is found in both the cell nucleus and the mitochondria. Most of a person’s DNA is nuclear DNA because it is found in the nucleus; small portions of DNA can also be found in the mitochondria, giving this type the name mtDNA or mitochondrial DNA. DNA has many properties; one of its most important is that it can copy itself. When this process occurs, the double helix strands of DNA are used as a pattern for replicating the base sequences. This is crucial during cell division due to the imperative need for each new cell to carry a precise copy of the DNA found in the old cell.
Adenine (A), thymine (T), guanine (G), cytosine (C) and uracil (U) are five out of about three billion chemical bases that store DNA’s coded information; over 99% of these bases have been found to be consistent in all people. The sequence of the bases is extremely important because the order that they are found in, reveals the information necessary and accessible for creating and upholding an organism. A simple way to comprehend this explanation is that DNA works in similar ways to alphabet letters; letters are put in certain orders to form a word or sentence and if they were to be mixed up, they would have a much different meaning. DNA is composed of two long strands that form a spiral made up of nucleotides called a double helix. The nucleotides that form this double helix are composed of a base attached to a sugar, and phosphate. The bases found in the double helix pair up with each other, T with A and G with...

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