phytoplankton

American  

[fahy-tuh-plangk-tuhn] / ˌfaɪ təˈplæŋk tən /

noun

1. the aggregate of plants and plantlike organisms in plankton.

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phytoplankton British  

/ ˌfaɪtəˈplæŋktən, ˌfaɪtəplæŋkˈtɒnɪk /

noun

1. the photosynthesizing organisms in plankton, mainly unicellular algae and cyanobacteria Compare zooplankton

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phytoplankton Scientific  

/ fī′tō-plăngk′tən /

1. Plankton consisting of free-floating algae, protists, and cyanobacteria. Phytoplankton form the beginning of the food chain for aquatic animals and fix large amounts of carbon, which would otherwise be released as carbon dioxide.

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Other Word Forms

• phytoplanktonic
  adjective

Etymology

Origin of phytoplankton

First recorded in 1895–1900; phyto- + plankton

Explanation

Tiny plants that live near the surface of the ocean and are too small to see are phytoplankton. Many small sea creatures, like krill, feed on phytoplankton. Yum! The word phytoplankton comes from Greek roots: phyton, "plant," and planktos, "wandering or drifting." Much plankton is composed of tiny animals, but the plankton made up of plants is phytoplankton. These microscopic organisms drift along close enough to the ocean's surface to photosynthesize, absorbing light and making their own food. Phytoplankton are an important part of the food chain — they're eaten by krill, which are eaten by baleen whales.

Example Sentences

Phytoplankton, tiny photosynthetic organisms in the ocean, play a crucial role in the global carbon cycle and influence Earth's climate.

From Science Daily • Oct. 13, 2023

Phytoplankton across the Southern Ocean are increasingly starved of iron—a building block for their photosynthetic machinery—and there are signs their productivity might be declining.

From Science Magazine • Feb. 22, 2023

Phytoplankton, sometimes described as an “invisible forest,” are tiny plant-like organisms that serve as food for marine life.

From Washington Post • Jan. 19, 2023

Phytoplankton release over 50% of the carbon dioxide produced on Earth through photosynthesis.

From Textbooks • Jun. 9, 2022

Phytoplankton, commonly referred to as algae, are a keystone food source for countless marine creatures, from clams to baleen whales.

From Scientific American • Jan. 24, 2022