P1 - topic 2 - gamma rays and ionising radiation Flashcards
why can gamma rays be used to treat cancer?
high doses of gamma rays will kill all living cells
how do gamma rays treat cancer?
they are directed carefully and at just the right dosage so as to kill the cancer cells without killing too much normal cells
Why do patients being treated for cancer feel ill?
the treatment still does a fair bit of damage to normal cells
what kind of rays can be used to diagnose cancer?
gamma rays
How do gamma rays diagnose cancer?
A radioactive isotope is injected into the patient - a gamma camera is then used to detect where the radioactive isotope travels in the body which creates an image which can then be used to detect where there might be cancer
sterilisation of food and surgical instruments uses what?
y rays
why can food be exposed to high doses of gamma rays?
it kills microbes, keeping the food fresh for longer
why is medical instruments exposed to high doses of gamma rays?
it sterilisers it but killing all microbes
what is an advantage of irradiation over boiling?
it doesn’t involve high temperatures so things like apples can be sterilised without damaging them
what needs to be a very strong emitter of gamma rays when sterilising?
the radioactive isotope used
how many types of ionising radiation is there?
3
what are the three types of ionising radiation?
gamma rays
alpha particles
beta particles
ionising radiation is emitted all the time by what?
radioactive sources when their nuclei decay
emission are completely random but when it does Halle. what does the nuclei do?
spit out one or more of the three types of i noisily radiation - gamma rays, beta, alpha
does ionising radiation transmit energy?
yes
