green alga

American  

[green al-guh] / ˈgrin ˈæl gə /

noun

plural

green algae

1. any one species of the green algae, the grass-green, chiefly freshwater algae of the phylum Chlorophyta, often growing on wet rocks, damp wood, or on the surface of stagnant water.

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green alga Scientific  

1. Any of various photosynthetic protists belonging to the phylum Chlorophyta. The green algae share many characteristics with plants, notably in their having chlorophylls a and b, in their storage of food as starch, and in the composition of their cell walls from cellulose or other polysaccharides. The green algae show a great variety of body types, ranging from unicellular forms to filaments to leaflike thalli, and many species live in colonies. Green algae also show a variety of reproductive processes, both sexual, by the formation of conjugating gametes or the exchange of nuclei through conjugation tubes, and asexual, by means of spores. Green algae are mostly aquatic, in both freshwater and marine environments. However, many species live on land or in the soil, and even in extreme environments, such as the surface of snow. Green algae are not always green, since they produce carotenoid pigments that can give them orange or red colors. Some lichens consist of a symbiotic relationship between a fungus and a green alga. Sea moss and the common pond scum Spirogyra are green algae.

2. Also called chlorophyte

3. See more at alga

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Other Word Forms

• green algal adjective

Example Sentences

To investigate, the research team turned to Codium fragile, a type of marine green alga.

From Science Daily • Oct. 22, 2025

For example, the haploid green alga Chlamydomonas reproduces asexually by mitosis, but when environmental conditions become unfavorable, it can reproduce sexually.

From Textbooks • Jan. 1, 2018

Take a look at this video to see cytoplasmic streaming in a green alga.

From Textbooks • Jan. 1, 2015

C. nivalis is a green alga — the group that gave rise to land plants, and includes the desmids I discussed here last month.

From Scientific American • Jul. 9, 2013

And on the face of the matter there is no ground for refusing to admit that Heteromita may be related to Chlamydomonas, as the colourless fungus is to the green alga.

From Discourses Biological and Geological Essays by Huxley, Thomas Henry