| Chrysophytes |
Microscopic, planktonic |
Diatoms: Silica cell walls; Golden algae: Cellulose cell walls |
Asexual (fission), sexual |
Diatomaceous earth (polishing, filtration) |
Diatoms (e.g., Thalassiosira), Golden algae (e.g., Desmidium) |
Chlorophyll a, chlorophyll c, fucoxanthin |
| Dinoflagellates |
Mostly marine, photosynthetic |
Cell wall with cellulose plates; Two flagella (longitudinal & transverse) |
Asexual (fission), sexual |
None (can be harmful in red tides) |
Dinoflagellates (e.g., Gonyaulax), Red tide organisms |
Chlorophyll a, chlorophyll c, peridinin |
| Euglenoids |
Freshwater, flexible body |
Protein-rich pellicle instead of cell wall; Mixotrophic (photosynthetic & heterotrophic) |
Asexual (fission) |
None |
Euglena (e.g., Euglena gracilis) |
Chlorophyll a, chlorophyll b, carotenoids |
| Slime Moulds |
Saprophytic, amoeboid movement |
Under suitable conditions, they form an aggregation called plasmodium which may grow and spread over several feet. During unfavourable conditions, the plasmodium differentiates and forms fruiting bodies bearing spores at their tips. The spores possess true walls. They are extremely resistant and survive for many years, even under adverse conditions. The spores are dispersed by air currents. |
Asexual (spores) |
None |
Slime moulds (e.g., Dictyostelium discoideum) |
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