Algae: Quick Facts

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Oct. 9, 2026

Facts

Also Known As	Phycophyta • algas • alga

Photos and Videos

“mermaid's wine glass” algae

Halimeda discoidea

Dead fish scattered along the sandy shore of Tampa Bay, Florida, with reddish and greenish water bands near the coast caused by a red tide dinoflagellate bloom.

Rectangular plots of seaweed farms with workers tending algae in shallow water on Nusa Lembongan, Indonesia, with a distant mountain visible in the background.

Highly magnified view of a single diatom, showing a circular, symmetrical structure with intricate radial patterns and a textured, translucent surface.

How phytoplankton function and survive in the ocean

Bright green algae blooms distort the surface of water.

Turning sewage into green crude oil: How does it work?

Take a microscopic look at how a eukaryotic flagellate's flagellum propels the organism through water

Dark reactions in photosynthesis explained

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Topics

Tasmanites Botryococcus Cryptophyta Euglenophyta hymenial algae Chromophyta Meet the Microbes: 5 Tiny Protozoans and Algae Dinoflagellate Seaweed Is seaweed a plant?fungus slime mold plant Protozoan ciliate Myxomycetes apicomplexan Plasmodiophoromycota Chytridiomycota rhizopod

Dig Deeper: More Articles That Discuss This Topic

Microbiology: Algae

Key People

Ferdinand Cohn

Ferdinand Cohn

German botanist

Dr. Sylvia A. Earle, wearing a red jacket, sits beside a small deep-sea submersible with a glass dome and camera equipment.

Sylvia Earle

American oceanographer and explorer

Hooker, Sir William Jackson

Sir William Jackson Hooker

British botanist

Nathanael Pringsheim.

Nathanael Pringsheim

German botanist

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Per Teodor Cleve

Swedish chemist

French botanist Gustave-Adolphe Thuret, c. 1867.

Gustave-Adolphe Thuret

French botanist

Mushrooms growing in forest. (vegetable; fungus; mushroom; macrofungi; epigeous)

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