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Ahmed El Sayed - ArticlesBiologyBiology is the science of life. It is concerned with the physical characteristics and behaviors of organisms alive today and long ago, how they come into being, and what interactions they have with each other and their environments.
The word biology in its modern sense seems to have been introduced independently by Gottfried Reinhold Treviranus (Biologie oder Philosophie der lebenden Natur, 1802) and by Jean-Baptiste Lamarck (Hydrogéologie, 1802). TelevisionsThe standard adopted by the US was called NTSC, which stood for National Television Standards Committee. NTSC is the television standard in the US, Canada, and Japan.
Germany developed the television standard called PAL, which stood for Phase Alternating Line, and introduced it in 1967. PAL is the television standard in the United Kingdom, much of Europe, Africa, Australia, and some parts of South America. Carcinogenesis and CancerCarcinogenesis is the creation of a cancer.
Cancer is, ultimately, a disease of genes. Typically, a series of several mutations is required before a cell becomes a cancer cell. We distinguish between oncogenes, which promote cancer when "switched on" by a mutation, and tumor suppressor genes, which prevent cancer unless "switched off" by a mutation.
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