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[foh-toh-ree-ak-tuh-vey-shuh n] /ˌfoʊ toʊ riˌæk təˈveɪ ʃən/
noun, Biochemistry
a process that repairs DNA damaged by ultraviolet light using an enzyme that requires visible light.
1945-50; photo- + reactivation Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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photo reactivation in Medicine

photoreactivation pho·to·re·ac·ti·va·tion (fō'tō-rē-āk'tə-vā'shən)
The activation by light of something previously inactive or inactivated.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Article for photo reactivation


restoration to the normal state, by the action of visible light, of the deoxyribonucleic acid composing the hereditary material in animal skin cells and plant epidermal cells damaged by exposure to ultraviolet light. The phenomenon is also called photoreactivation, especially in microorganisms. The failure of cells to repair such damage, in individuals with certain biochemical disorders, leads to serious skin problems.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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