Phytoplankton

Autotrophic members of the plankton ecosystem

Phytoplankton are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from Ancient Greek φυτόν (phutón), meaning "plant", and πλαγκτός (planktós), meaning "drifter, wanderer, roamer", and thus, "plant drifter". Phytoplankton obtain their energy through photosynthesis, as trees and other plants do on land.

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