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Glossary item | 12 February 2018


Algae, singular alga, members of a group of predominantly aquatic photosynthetic organisms of the kingdom Protista. Algae have many types of life cycles, and they range in size from microscopic Micromonas species to giant kelps that reach 60 metres (200 feet) in length. Their photosynthetic pigments are more varied than those of plants, and their cells have features not found among plants and animals. The taxonomy of algae is contentious and subject to rapid change as new molecular information is discovered.

Algae are eukaryotic (nucleus-bearing) organisms that photosynthesize but lack the specialized multicellular reproductive structures of plants, which always contain fertile gamete-producing cells surrounded by sterile cells. Algae also lack true roots, stems, and leaves—features they share with the avascular lower plants (e.g., mosses, liverworts, and hornworts). Additionally, the algae as treated in this definition exclude the prokaryotic (nucleus-lacking) blue-green algae (cyanobacteria).

Lewin, Ralph A. and Andersen, Robert A.. "Algae". Encyclopedia Britannica, 11 Feb. 2021. Accessed 26 March 2021

Source category: Scientific & Technical Literature

Algae strain is defined as population of unicellular/pluricellular organisms of a single algae species, all descended from the entirety/or a part of an organism or several organisms, being synonymous with a monoclonal culture and a genetic representative of a single algae species.

This standard defines the terms related to functions, products, and properties of algae and algae products. In order to better pack the methodologies, algae are regarded as a functional group of organisms consisting of microalgae, macroalgae, cyanobacteria and Labyrinthulomycetes.

Algae and algae products - Terms and definitions. CEN/TC 454 - Algae and algae products. 2020

Source category: Standards

Algae refers to a diverse mix of organisms from different kingdoms of life. Traditionally, algae have been unified based on their ability to carry out photosynthesis and live in aquatic habitats. Algae include microalgae (unicellular eukaryotic organisms), macroalgae (seaweeds), and cyanobacteria (historically known as blue-green algae).

US DOE, 2010, National Algal Biofuels Technology Roadmap. U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Biomass Program, Washington D.C.

Source category: Scientific & Technical Literature

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