The word Symbiosis is formed from the Greek words Sym meaning together and bios meaning living. If two organisms of different species living together do not harm each other, but only benefit, then it is called Symbiosis or Mutualism. Algae and fungi form mythos. The algal member is called the phycobiont or photobiont and the fungal member is the mycobiont. Both algae and fungi benefit from mitosis. Mythology explained.