Symbiotic Relationships Symbiosis refers to an intimate relationship between two organisms. This term does not indicate whether the relationship is beneficial or harmful to teh organisms involved. Mutual symbiosis, or mutualism, occurs when both species g

Symbiotic Relationships Symbiosis refers to an intimate relationship between two organisms. This term does not indicate whether the relationship is beneficial or harmful to teh organisms involved. Mutual symbiosis, or mutualism, occurs when both species gain some benefit from the relationship, whereas parasitism consists of a relationship in which one of the organisms benefit, while the other one is harmed. A third symbiotic relationship is that of commensalism In commensalism, the relationship beneficial to one of the organisms while the other neither benefit nor is harmed. A commensal organism can be either obligate or facultative. The obligate commensal cannot survive without its symbiotic partner. The facultative commensal can be found either living with its symbiotic partner or on its own.