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 uses high-energy radiation to shrink tumors and kill cancer cells-X-rays, -gamma rays,-charged particles are types of radiation used for cancer treatment. The radiation may be delivered by 1. a machine outside the body (external-beam radiation therapy) 2. It may come from radioactive material placed in the body near cancer cells (internal radiation therapy, also called brachytherapy). 3.