Uses Of Radiation Flashcards
How do tracers in medicine use radiation?
Certain radioactive isotopes can be injected into people and their process around the body is followed using an external detector. Computer converts display showing where highest reading comes from
What is an example of radiation in medicine tracers?
Iodine -131 is absorbed by the thyroid gland and it gives out radiation which can be detected to see if the thyroid gland is taking in iodine as it should
What should all isotopes in the body be?
Gamme or beta emitters (never alpha) so the radiation passes out of the body quickly
Why can gamma rays be used to treat cancer?
High doses of gamma rays will kill all living cells
Why do gamma rays have to be directed carefully and at just the right dosage?
To kill the cancer cells without damaging too many normal cells
Damage is still done to normal cells, what is the effect of this?
Makes the patient feel very ill but if the cancer is killed off it’s worth it
How is radiation used in food?
Food can be exposed to a high dose of gamma rays which will kill all microbes keeping the food fresh for longer
The food is not radioactive afterwards so it’s safe to eat
How is radiation used on medical equipment?
It can be used to sterilise them instead of boiling them
What is the advantage of irradiation over boiling?
It doesn’t involve high temperatures so things like fresh apples and plastic instruments can be totally sterilised without damaging them
What does the isotope used for sterilising need to be?
Very strong Emitter of gamma rays with a reasonably long half life so it doesn’t need replacing too often
How is radiation used in smoke detectors?
Alpha particles from Americum 241 ionise air to make ions and electrons
Current flows between two charged plates when smoke gets in the air gaps current falls and the alarm sounds
