YOU ARE LEARNING:
Tissue Damage and Mutations
Tissue Damage and Mutations
Ionising radiation can cause damage to living cells, which can lead to DNA mutations and potentially cancer.
Radiation can be dangerous. What kind of radiation is most harmful?
Nuclear radiation is ionising radiation, so it can be harmful. But why is ionising radiation more harmful than non-ionising radiation?
What do we call the material inside the cell nucleus that contains our genetic code?
So radioactive materials can be dangerous because they emit ionising radiation that can damage for example our DNA! This can lead to _____________ and _____________.
You can select multiple answers
To recap
Radioactive materials can be dangerous because they emit ionising radiation
Ionising radiation can enter our cells and damage them!
For example, it can damage our DNA
This can lead to mutations, or in rare cases to cancer.
Very high doses of radiation can destroy cells completely
This can cause radiation poisoning.
Now, how damaging is ionising radiation?
That depends on both the kind of radiation and the dosage of radiation you are exposed to.
The kind of radiation matters for how dangerous it is.
First of all, what kind of radiation is the most ionising?
True or false? Alpha radiation is the most ionising, but it is not necessarily the most harmful form of radiation.
So alpha radiation is the most ionising form of radiation
But it is not always the more hazardous kind. That depends on where the radiation source is compared to your body, because different forms of radiation have different penetrating power.
Which radiation is the most penetrating?
So alpha radiation is the most ionising and gamma radiation is the most penetrating. So if a source of radiation is outside the body, it will be more harmful if it is...
Gamma and beta radiation are the more dangerous external sources of radiation because they can penetrate our skin
Alpha radiation is more ionising, but it is the least harmful kind as an external source because it gets stopped by a short distance of air, and it can't penetrate our skin.
Now, what if you ate some form of radiation? Which form would be the most dangerous?
As an internal source of radiation, alpha radiation would be more dangerous
The alpa particles would be able to damage your cells from the inside where the skin does not protect them.
The dosage of radiation matters for how dangerous it is.
The dosage, or the amount of radiation you are exposed to, depends on 3 factors. Which 3, do you think?
You can select multiple answers
If we want to know how radioactive a substance is, we need to look at its ____________.
Summary
Ionising radiation can cause damage to our cells
If our DNA gets damaged, it can result in mutations and maybe even cancer.
How damaging a form of radiation is depends on two things
The kind of radiation you are exposed to as internal or external sources. The dosage (amount) of radiation you are exposed to.
Alpha radiation...
is very highly ionising, so if it is an internal source (inside your body), it's very dangerous!
Beta and gamma radiation...
are not as highly ionising as alpha radiation, but they are more penetrating. They can penetrate your skin, so they are more dangerous as external sources than alpha radiation.
The dosage of radiation depends on 3 factors
How radioactive a substance is (its half-life). How long you are exposed to it. How far away it is.