Radiation is more readily absorbed by actively growing cells. How is this both useful and dangerous?

The fact that radiation is more readily absorbed by
actively growing cells is very useful in the treatment of cancers. Radiation treatment
uses high power radiation which is applied to the organ that has cancer. An important
characteristic of cancerous cells is that they develop and reproduce at a faster rate
than normal cells.

When radiation is used, it damages the
DNA of cells which form the affected organ; the cancerous cells are damaged more due to
their fast rate of growth. Normal cells which reproduce at a slower rate are not
affected as much as the diseased cells and recover within a short period of the
radiation treatment.

But the absorption of radiation by
actively growing cells makes it very injurious to newly born babies and those in the
mother's womb. This is a reason why pregnant women are not advised to undergo radiation
therapy.