Final answer:
The primary difference between mutualism and parasitism is that parasitism is harmful to one species, while mutualism benefits both species.
Step-by-step explanation:
The primary difference between mutualism and parasitism is that parasitism is always harmful to one of the species involved, while mutualism benefits both species. In parasitism, one organism, the parasite, benefits at the expense of the other organism, the host. The parasite gains nutrients or resources from the host, whereas the host is negatively affected. On the other hand, mutualism is a type of symbiotic relationship where both species benefit from their interaction. They rely on each other for survival, such as in the case of pollination, where bees benefit from nectar while plants benefit from pollination and reproduction.
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