Radiation can damage DNA molecules in three ways: by causing a single strand break, a break in both strands, or a chemical change or mutation. A single strand break can often be repaired by the cell. The other two types of damage usually cannot be repaired.
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Can living cells repair damage from radiation?
Whether or not a cell can repair itself after being damaged by radiation depends on the type of damage to the cell's DNA.
| Type of Damage
|| Prospects for DNA Repair
| Single strand break in the DNA
||Can usually be repaired and normal cell function restored.
| Breaks in both DNA strands
||Usually damage is too severe for repair. The cell dies.
| Chemical change or mutation
||Cannot be repaired. Cancer may result or a mutated offspring if this occurs in a sperm or egg cell.
Cells (such as those contained in the skin, eyes and blood-forming organs [BFO]) that reproduce rapidly are the most susceptible to damage because they cannot repair themselves easily while replicating. Acceptable radiation doses are usually given separately for these organs.
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