This process is known as photosynthesis and the most famous of these pigments are chlorophyll a and chlorophyll b . UV is something to be wary of, but x and gamma rays are worse. Of course, particles with energies greater than this are even more dangerous, but their existence on earth is extremely rare under normal circumstances. Any radiation that can disrupt the normal chemistry of a cell is dangerous to living things. There are three mechanisms by which nuclear radiation can do this.
Energetic particles leave a trail of ions in their wake.
Neutron Absorption . The absorption of a neutron into the nucleus of an atom may result in the formation of an unstable isotope and its transmutation into a different element. If the energy of an incident particle is sufficiently high it can displace an atom from its position in a molecule. In extreme cases a cell could be killed outright, but there are more subtle forms of damage. Altering a DNA sequence that controls growth may cause the cell to grow without limit.