Mechanism of Radiation Damage (p.98)

Date: 2015-10-07; view: 350.

1. Any material undergoes some damage or change on irradiation.

2. In elements the only effect is a change of the crystal structure.

3. Living organisms undergo chemical change.

4. Ionizing radiations pass through living matter and split the water into chemically very active parts or ions.

5. They can react in turn with other important molecules in cells.

6. These important molecules are nucleic acids determining the heredity of the cell or mutations.

7. Mechanism of radiation damage falls into two main groups – direct action and indirect one.

8. Direct action is the breaking of some part of the cell structure by the bombarding particles or photons.

9. They may damage the action of the cell or part of the cell, having a specific function (gene).

10. In indirect action no part of the cell is damaged directly.

11. Very active groups of atoms called free radicals are formed.

12. They come into contact with nearly molecules and break the cell function.

13. Biochemical reactions are changed blood composition, brain function. This results in the breaking of cell division.

14. Thus the mechanism of the radiation damage has the following steps:

a) radiation energy absorption

b) free radicals formation

c) the breaking of biochemical reaction

d) the breaking of physiological reaction