Parasitism define

Parasitism is a relationship in which one organism benefits while the host is harmed. The parasite depends on the host for resources or another advantage. The harm can vary in kind and degree rather than always causing immediate death.

Meaning and context

This differs from mutualism, where both partners benefit, and from commensalism, where one benefits without a meaningful effect on the other in the simplified model. Real relationships can be more complex than the introductory categories suggest.

Examples and usage

A tick feeding on a mammal is a familiar parasitism example. The tick gains resources, while the host can experience costs. That example explains the relationship and does not mean every host has the same outcome.

What to check

Keep the ecological definition separate from diagnosis. A symptom or an online image cannot establish a particular parasite in a person or animal. For a biology exercise, identify the organisms, the benefit, and the host cost that support the classification.

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