Final answer:
Mutualism is a symbiotic relationship in which both species benefit, while commensalism is a symbiotic relationship in which one species benefits while the other is not affected. Parasitism is a symbiotic relationship in which the parasitic species benefits while the host species is harmed.
Step-by-step explanation:
Mutualism is a symbiotic relationship in which both species benefit. Commensalism is a symbiotic relationship in which one species benefits while the other is not affected. Parasitism is a symbiotic relationship in which the parasitic species benefits while the host species is harmed.