How Can Radiation Hurt a Living Cell?

The Key to the Destructive Power of Radiation:

High frequency radiation or fast moving particles plow into a living cell with enough energy to knock electrons free from molecules that make up the cell. These molecules with missing electrons are called ions. The presence of these ions disrupts the normal functioning of the cell.

The most severe damage to the cell results when the DNA (deoxyribonucleic acid) is injured. DNA is at the heart of the cell and contains all the instructions for producing new cells. The DNA is a complex molecule formed of two long strands that are twisted around each other and linked by chemical subunits.

There are two major ways that radiation injures the DNA inside your cells:

  • The water in your body tends to absorb a large portion of the radiation and becomes ionized. When water is ionized it readily forms highly reactive molecules called free radicals. These free radicals can react with and damage the DNA molecule.
  • Alternatively radiation can collide with the DNA molecule, itself, ionizing and damaging it directly.

Symptoms of radiation sickness: severe burns that are slow to heal, sterilization, cancer, and other damage to organs. High doses are rapidly (within days or weeks) fatal.

Mutations or changes in the DNA can be passed along to offsprings. Mutations are generally for the worse.

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