If this tissue forms a specialised functional unit, it is called an organ. These radicals can contribute to the destruction of the cell.Ī large number of cells of any particular type is called a tissue. Ionizing radiation may break the bonds that hold the water molecule together, producing radicals such as hydroxyl OH, superoxide anion O 2 –and others. Each cell, just as is the case for the human body, is mostly water. Indirect effects are caused by interaction of radiation usually with water molecules. The probability of the radiation interacting with the DNA molecule is very small since these critical components make up such a small part of the cell. Direct effects are caused by radiation, when radiation interacts directly with the atoms of the DNA molecule, or some other cellular component critical to the survival of the cell. These two mechanisms are commonly called: There are two mechanisms by which radiation ultimately affects cells. Simply ionizing radiation can knock electrons from an atom. For ionizing radiation, the kinetic energy of particles ( photons, electrons, etc.) of ionizing radiation is sufficient and the particle can ionize (to form ion by losing electrons) target atoms to form ions. Although we tend to think of biological effects in terms of the effect of radiation on living cells, in actuality, ionizing radiation, by definition, interacts only with atoms by a process called ionization. Every part of your body consists of cells or was built by them. All living things are composed of one or more cells. Cellular Damage – RadiobiologyĪll biological damage effects begin with the consequence of radiation interactions with the atoms forming the cells. This chapter briefly summarizes the short and long term consequences which may result from exposure to radiation. In general, ionizing radiation is harmful and potentially lethal to living beings but can have health benefits in medicine, for example, in radiation therapy for the treatment of cancer and thyrotoxicosis. Whether the source of radiation is natural or man-made, whether it is a large dose of radiation or a small dose, there will be some biological effects. It is a part of our natural world that has been here since the birth of our planet. It is a natural energy force that surrounds us. In, around, and above the world we live in. Stuart, C.I.J.M.: 1985, ‘Bio-Informational Equivalences’, Journal of Theoretical Biology 113, 611–636.Radiation biology (also known as radiobiology) is a medical science that involves the study of biological effects of ionizing radiation on living tissues. Short, T.L.: 1982, ‘Life Among the Legisigns’, Transactions of the Charles S. Short, T.L.: 1981, ‘Semiosis and Intentionality’, Transactions of the Charles S. Peirce on Biological Evolution and Scientific Progress’, Synthese 41, 85–114. (ed.): 1986, Encyclopedic Dictionary of Semiotics, Vol. Rosenberg, A.: 1985, The Structure of Biological Science, Cambridge University Press, Cambridge. Rieppel, O.: 1990, ‘Structuralism, Functionalism, and the Four Aristotelian Causes’, Journal of History and Biology 23(2), 291–320. Peirce, C.S.: 1955, Philosophical Writings of Peirce (ed.: J. Burks)fs, Harvard University Press, Cambridge, Mass. Peirce, C.S.: 1931–1958, Collected Papers of Charles Sanders Peirce (eds.: C. Pattee, H.H.: 1977, ‘Dynamic and Linguistic Modes of Complex Systems’, International Journal of General Systems 3, 259–266. Nagel, E.: 1977, ‘Teleology Revisited’, The Journal of Philosophy 74(5), 261–301. VI), Addison-Wesley Publishing Co., Redwood City, Calif. (ed.): 1989, Artificial Life, (Santa Fe Institute Studies in the Sciences of Complexity, Vol. The Life and Work of Barbara McClintock, Freeman, San Francisco. Keller, E.F.: 1983, A Feeling for the Organism. Jakobson, R.: 1973, Main Trends in the Science of Language, George Allen and Unwin, London. Merrell (eds.), On Semiotic Modelling, Mouton de Gruyter, Berlin (in press). Emmeche: 1990, ‘Code-Duality and the Semiotics of Nature’, in M. Haugeland, J.: 1985, Artificial Intellegence: The Very Idea, The MIT Press, Cambridge, Mass. Dictionaire raisonné de la théorie du language, Hachette, Paris. The Development of Peirce's Theory of Categories, Ohio University Press, Ohio.įoucallt, M.: 1970, The Order of Things: An Archaeology of the Human Sciences, Tavistock, London. Sebeok, T.A., Uexküll, T.V.: 1984, ‘A Semiotic Perspective on the Sciences: Stept Toward a New Paradigm’, Semiotica 52(1/2), 7–47.īurks, A.W.: 1988, ‘Teleology and Logical Mechanism’, Synthese 76, 333–370.Ĭlarke, D.S, Jr.: 1987, Principles of Semiotic, Routledge and Kegan Paul, London.Įsposito, J.L.: 1980, Evolutionary Metaphysics. Anderson, M., Deely, J., Krampen, M., Ransdell, J.
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