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noun, plural: dinoflagellates

Any of the many photosynthetic aquatic organisms characterized by having two flagella of unequal length arising from the ventral cell side (i.e. one of the flagella is lying in the groove around the body and the other is extending from the center), an armor-like shell or pellicle, a dinokaryon, and dinoflagellate toxin


Photosynthetic organisms of the order dinoflagellida (for botanists Dinophyceae). They are aquatic and have 2 flagella lying in grooves in an often elaborately sculptured shell or pellicle that is formed from plates of cellulose deposited in membrane vesicles. The pellicle gives some dinoflagellates very bizarre shapes. Their chromosomes lack centromeres and may have little or no proteinand may perhaps be intermediate between pro and eu karyote types, hence the group has been termed mesokaryotic. The nuclear membrane persists during mitosis. They are very abundant inmarine plankton. Gymnodinium and Gonyaulax, that causes red tide, produce toxins that if accumulated by filter feeding molluscs can be fatal. Another common genus is Peridinium. Food reserve is stored in form of starch like carbohydrates and oils. A noncontractile vacuole called pustule is present near the flagellar base. It may have one or more vesicles. Pustule may take part in floatation and osmoregulation. Contractile vacuoles are absent.

Word origin: Ancient Greek dînos (“whirling”) + flagellate

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