Free Radical Mitochondria Research Paper

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Free radicals are highly reactive atoms or polyatomic ions that have unpaired valence electrons. These unpaired electrons can bind to organic compounds, changing the structure of the substance (Halliwell, B.). In most cases, oxygen-free radicals (OFRs) and reactive oxygen species (ROSs) are byproducts of metabolism. OFRs originate from the metabolic process in mitochondria when oxygen molecules accept an extra electron (Raha, S. et al). While oxygen is necessary for respiration, OFRs can bind to cellular components like DNA bases or the deoxyribose backbone of DNA, which plays a key-role in the aging process and is also linked to the development of certain cancers (Valko, M. et al). The ability of OFRs and ROSs to bind to DNA causes breaks in the structure of DNA and is the reason why these …show more content…

This process oxidizes reduced compounds and reforms ATP to release energy. The process normally creates water as a by-product, but it also normally produces free radicals. As electrons travel throughout the respiratory chain, they can escape and bind to electron acceptors, like O2, which generates free radicals (Lagouge, M. et al). While the production of these free radicals is inevitable, there are defense mechanisms in place to target these radicals and deactivate them, known as antioxidants. The superoxide is converted to hydrogen peroxide, which can be broken down by enzymes collectively known as superoxide dismutases into water (Raha, S. et al). Other ROS scavengers such as carotenoids and flavonoids can also inactivate ROSs. Oxidative stress is therefore the result of an imbalance of enzymatic and nonenzymatic detoxification of ROSs (Lagouge, M. et al). This imbalance is normally very low due to the effectiveness of dismutases. However, certain conditions can increase the imbalance, such as ingested toxins that increase the production of free radicals and long periods of increased oxygen

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