Radiation can damage the DNA in the cells of living things. Damaged DNA can make the cell stop working or unable to reproduce. It can also cause the cell to grow out of control, causing cancer.
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Radiation is Dangerous to Living Creatures
Radiation can be harmful to living creatures. Radiation can harm living things directly by damaging their cells. The cells might stop functioning, or they might be unable to reproduce. Radiation can also cause cells to reproduce in an out-of-control fashion, causing cancer.
Radiation can also interfere with the reproduction of living things. It can cause sterility, making reproduction impossible. It can also cause mutations in offspring, which are usually detrimental or even fatal.
Animals (including humans) tend to be more susceptible to the harmful effects of radiation than plants. Some types of microbes are tolerant of high doses of radiation that would easily kill multicelled organisms.
Natural sources of radiation play a role in the long-term evolution of species. Some (a very, very tiny fraction) mutations caused by radiation turn out to be beneficial. They give certain organisms a better chance to survive. Sometimes mutations caused by radiation produce a more successful and better-adapted new species.
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