Biological Effects Flashcards
Given various amounts of radiation dose and sources of radiation (including natural and man-made), DETERMINE the biological risk to an exposed individual.
What is the average annual radiation dose to the general population of the US from natural background & man-made sources?
620 mrem
What are the 4 main sources of naturally occurring radiation exposures?
- Cosmic radiation
- Terrestrial sources (in earth’s crust)
- Internal sources (in body)
- Radon & other daughter products
IDENTIFY the method by which radiation damages cells: Radiation damages cells by _____ the atoms that make up the cell components.
ionizing
Any potential radiation damage begins w/ damage to atoms. Radiation damages cells and may cause ____. This is where the radiation deposits energy into an atom, raising its energy level but not enough to eject a bound electron.
excitation
Actively dividing cells are more _____ to ionizing radiation. More specialized or slower dividing cells like adult brain cells are less _____.
sensitive x 2
IDENTIFY the possible effects of radiation on cells: there are ____ things that can occur.
4
1/4 possible effect of radiation on cell: most cells are made primarily of water, and this is what ionizing radiation is most likely to interact with, causing hydrogen peroxide to form which is poisonous to cell. If this is the case, the cell can _____ _____.
repair itself
2/4 possible effect of radiation on cell: if a cell chromosome is damaged, does not repair correctly, & continues to reproduce - this is called a _____ & may result in cancer.
mutation (i.e., cell damage)
3/4 possible effect of radiation on cell: while it is routine for our cells to die & be replaced continually, a contributing factor to ____ ____ might be radiation exposure.
cell death
If an individual receives _____ (range) rad of exposure, the effects are not detectable through symptoms or blood tests.
0-25
Detectable changes in blood occur at a rad exposure of ______ (range).
25-100
If an individual receives _____ (range) rad of exposure, they will experience nausea, vomiting, & loss of appetite.
100-300
If an individual receives _____ (range) rad of exposure, this can cause diarrhea, hemorrhage, & potentially death.
300-600
_____ rad is considered the dose where 50% of fatalities occur w/ in 60 days w/o medical help.
450 (LD 50/60)
A typical example of ______ radiation dose is the dose we receive f/ natural background, man-made radiation or occupational exposure.
chronic
Biological Effects: ______ effects of radiation exposure appear in the exposed person and are further divided into 2 classes - _____ & delayed effects.
Somatic / prompt
Biological Effects: ______ somatic effects are those that may occur years after radiation doses are received. This includes the increased potential for development of _____ & cataracts.
Delayed / cancer
Biological Effects: _____ effects are physical mutations or traits that are passed on to offspring. Even though these effects have never been observed in humans, they are considered _____.
Heritable / possible
The embryo/fetus is most susceptible to developing adverse health effects if exposed during the time period of _____ (range) weeks after conception.
8-15
Some of the potential effects associated w/ prenatal radiation doses include (1) ______, (2) lower _____ birth weight, and (3) higher likelihood of _____ disability.
smaller head size / average / intellectual
2 examples of radiation exposure which are considered to be chronic radiation doses are natural ______ radiation or man-made radiation & ______ exposure.
background / occupational
What is the process by which radiation causes damage to cells?
IONIZATION
