Biology / Unit 14 Bio 3595 short lesson, about 20 seconds
Symbiosis: Mutualism, Commensalism, and Parasitism
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The idea
Symbiosis is a close, long-term relationship between two species: mutualism when both benefit, commensalism when one benefits and the other is unaffected, parasitism when one benefits at the other's expense.
In practice
A tapeworm consuming a host's nutrients is parasitism; a bird nesting harmlessly in a tree is commensalism.
Where people slip
Symbiosis names any close relationship — it does not specify which outcome applies.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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