GCSE SCIENCE PHYSICS HIGH SCHOOL - Radioactivity - Damage to Living Cells - Cancer - DNA - Mutation - Intensity - Exposure

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Damage to Living Cells - Cancer.

Ionising radiation can cause damage to the DNA in the nucleus of cells.
Ultraviolet waves and x-rays also cause the same kind of damage.
DNA is the name given to the long molecules in the nucleus in the
shape of a double helix which make up the genes and chromosomes.

If the radiation is of a high intensity and long exposure,
it will cause so much damage that the cell will die.
This is useful for the technique of sterilisation.

Low intensity radiation can cause small changes to the DNA
which may alter the cell without killing it.
A cell which has had its DNA changed is called a mutation.
Some mutations are harmless and make no difference to the organism,
some may be beneficial (good), and some may be harmful.

A harmful mutation will increase in number when the cell copies itself
by mitosis. The cells will continue to grow in an uncontrolled way
and may then spread to other parts of the body.
This is what is called cancer. The chance of radiation causing cancer
increases as the exposure and intensity increases.
Exposure means the length of time that the radiation hits you.
Intensity means the amount of radiation that is present.
Cancer can be treated using radiotherapy.

The three types of radioactivity cause different amounts of damage
depending on whether they are inside or outside of the body - continued.

Headings Radioactivity Search Questions

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