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Dna And The Human Body

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Each cell in the human body has the same exact genetic material, with a few exceptions, and yet each cell does something different than all the other cells. Contained within the nucleus, the entire genome can be found, and within the genome, there is all the information needed to construct a specific organism. The genome is composed of deoxyribose nucleic acids, also called DNA, which breaks down into smaller units called genes. A gene has a specific sequence of adenine, thymine, cytosine, and guanine molecules that will code for a specific polypeptide. Polypeptides can then go on to become proteins for the cell to use. The genome is the same in every cell, but with about 200 different cell types, there must be something telling the …show more content…

Such things (include?)like the histone modification or methylation of DNA. Some sources debate that ‘epigenetics’ refers to all environmental factors which cause the alterations to occur. Things like the smoke from cigarettes, the food that you eat, the environment inside the placenta, you amount of sleep you get, and your exercising habits[3]. As epigenetics becomes more prominent in science, the debate evolves and the definition changes. Scientists are considering the effects of these epigenetic modifications as well as what creates the modifications. Several mechanisms cause these alterations to gene expression. The most commonly considered factors are DNA methylation, histone modification, and the effects of non-coding RNA. With DNA methylation, methyl groups (CH3) are added directly to the DNA. These methyl groups attach to the fifth carbon of the cytosine nitrogenous base by a protein called DNA-methyltransferase. The most common location for these methylations is at CpG sites, which are locations with a high amount of cytosine-guanine base pairs. The methylated cytosine is called a 5-methylcytosine (5-mc)[4]. The bound methyl group protrudes into the major grove of the DNA double helix and does not allow for any proteins to bind. DNA can either be hypermethylated, with a high number of methyl groups attached, or hypomethylated, with a low number of methyl groups attached. Hypermethylation typically causes genes to

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