bacterioplankton bak-TEER-ee-oh-PLANK-tun
noun.

plankton made of bacteria.

phytoplankton (fi-toh-PLAYNK-tun)
noun.

microscopic organism that lives in the ocean and can convert light energy to chemical energy through photosynthesis.

plankton (PLANK-tun)
plural noun.

(singular: plankton) microscopic aquatic organisms.

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toxic phytoplankton (TAHK-sihk FI-toh-plank-tun)
noun.

aquatic organism that produces chemicals that, in large amounts, can be deadly to plants and animals.

virioplankton VI-ree-oh-PLANK-tun
noun.

plankton made of viruses.

zooplankton (zoo-uh-PLAYNK-tun)
plural noun.

microscopic, heterotrophic organism that lives in the ocean.