Parasitism- a symbiotic relationship between two organism in which one species benefit for growth and reproduction to the harm of the other.
An example of a parastitism is in plant called Dodder.
It is also in an animal called bilharzoa
commensialism - is any relationship between two species in which one species benefit and the other neith benefits or harms.
Example is a clown fisn, who live with vaving mass of tentacles of sea anemones
Mutualism- is any relationship between two species of organims that benefit both species. example is ant, smallfish, lichens etc