Radiobiology > Physical Processes > Atomic and Molecular Interactions > Introduction (cont.)
Electromagnetic Energy Interactions
Photons interact with subatomic structures in one of the following three ways:
The particular type of interaction reflects probability statistics based on both the energy of the photon and the atomic number of the traversed atom. For most tissues of the body, average atomic number does not vary greatly - though cortical bone has the highest effective atomic number.