What are the relationships between organisms called symbiosis and parasitism?

Symbiosis is a type of interspecific relationship in which both organisms receive mutual benefit. Examples of symbiosis: hermit crab and sea anemone, nodule plants and bacteria, cap mushrooms and trees, lichens (symbiosis of fungus and algae)
Parasitism is a form of interspecific relationships in which some organisms exist at the expense of others, eating their blood, tissues, or digested food. Repeated use by a parasite of the host organism. Examples of parasitism: fungus and tree, dog and tick, parasitic worms and humans.

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