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Showing results for "alga"

alga

American  
[al-guh] / ˈæl gə /

noun

  • algae,
    plural
  • algas
    plural
  1. any organism belonging to one of the numerous groups of algae.


alga Scientific  
/ ăl′gə /
  • algae
    plural
  1. Any of various green, red, or brown organisms that grow mostly in water, ranging in size from single cells to large spreading seaweeds. Like plants, algae manufacture their own food through photosynthesis and release large amounts of oxygen into the atmosphere. They also fix large amounts of carbon, which would otherwise exist in the atmosphere as carbon dioxide. Algae form a major component of marine plankton and are often visible as pond scum and blooms in tidal pools. Land species mostly live in moist soil and on tree trunks or rocks. Some species live in extreme environments, such as deserts, hot springs, and glaciers. Although they were once classified as plants, the algae are now considered to be protists, with the exception of the cyanobacteria, formerly called blue-green algae. The algae do not form a distinct phylogenetic group, but the word alga serves as a convenient catch-all term for various photosynthetic protist phyla, including the green algae, brown algae, and red algae.


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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

"More than 80 fish were observed around a single floating alga," said Mr Mazoudier.

From Science Daily ● Jan. 31, 2024

Blue-green algae is not actually an alga but rather a type of bacteria called cyanobacteria.

From BBC ● Jul. 10, 2023

In the case of Gracilaria, however, things are more complicated: The female alga doesn’t release its egg cells, but keeps them inside funnel-shaped filaments.

From Science Magazine ● Jul. 27, 2022

Giant kelp is the common name for Macrocystis pyrifera, a species of alga that grows into lush underwater forests along the coast of the northeastern Pacific Ocean, from Baja California north to southeastern Alaska.

From Scientific American ● Jul. 21, 2022

She is curious; she wants to know the difference between an alga and a lichen, a Diplodon char- ruanus and a Diplodon delodontus.

From "All the Light We Cannot See" by Anthony Doerr

Then about 1.25 billion years ago, one of these photosynthesizing bacteria partnered with another one-celled organism to create green algae, one lineage of which became the ancestor of all plants.

From The Wall Street Journal ● Oct. 16, 2026

The key to the success of the method -- which the team informally dubbed "helping hands" -- is the transfer of healthy photosynthetic algae, also known as symbionts, from which corals derive their color.

From Barron's ● Oct. 14, 2026

A major new lawsuit argues the state is taking far too much water out of the Delta, harming native fish and the ecosystem, causing toxic algae blooms, and threatening local farms and communities.

From Los Angeles Times ● Oct. 9, 2026

Both are small, with cone-shaped shells measuring about 6 mm in length, and they live on limestone rocks where they feed on algae and lichens.

From Science Daily ● Sep. 24, 2026

Most of the banisters and railing had given way, and the floorboards had turned spongy and slick with mold and algae.

From "The Glass Castle" by Jeannette Walls

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