Generalities
5
1.1.2. Classification of microalgae
The biodiversity of microalgae is immense, reflected in the variety of shapes, sizes,
colors and habitats of these microorganisms. It has been estimated that there are around 200,000
species of microalgae on the planet. Some authors even put the figure at over a million species,
of which only 35,000 have been described (Rajkumar & Zahira, 2013; in Mortonen, 2017).
The genetic diversity and physiological plasticity of microalgae enable them to adapt to variable
environmental conditions, which explains the variety of species (Thruman & Burton, 1997).
1.1.2.1. Classification criteria
Microalgae are classified according to several criteria such as: the organization of their
photosynthetic membranes, the chemical nature of the reserve products derived from
photosynthesis (Carlsson et al., 2007), life cycle, basic cell structure and variation in
pigmentation (Chen et al., 2015). Table (1) lists some of the criteria used to classify microalgae.
5
1.1.2. Classification of microalgae
The biodiversity of microalgae is immense, reflected in the variety of shapes, sizes,
colors and habitats of these microorganisms. It has been estimated that there are around 200,000
species of microalgae on the planet. Some authors even put the figure at over a million species,
of which only 35,000 have been described (Rajkumar & Zahira, 2013; in Mortonen, 2017).
The genetic diversity and physiological plasticity of microalgae enable them to adapt to variable
environmental conditions, which explains the variety of species (Thruman & Burton, 1997).
1.1.2.1. Classification criteria
Microalgae are classified according to several criteria such as: the organization of their
photosynthetic membranes, the chemical nature of the reserve products derived from
photosynthesis (Carlsson et al., 2007), life cycle, basic cell structure and variation in
pigmentation (Chen et al., 2015). Table (1) lists some of the criteria used to classify microalgae.