Lichen is the symbiotic association of a fungus (the mycobiont, which provides shelter and structure for the partnership or symbiosis), with an alga or cyanobacterium (the phoâ¦tobiont, also known as the phycobiont, which provides the food for the partnership from photosynthesis).
Some radiation therapy delivery methods include: 1  External beam radiation therapy â radiation is directed from a machine outside the body onto cancerous cells within the body.  Internal radiation therapy â radioactive material is placed (via a catheter or other carrier) directly into or near a tumor.
Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It affects cells only in the part of the body that is treated with the radiation. Breast cancer radiation therapy may be used to destroy any remaining mutated cells that remain in the breast or armpit area after surgery.