Kingdom Protista

All single-celled eukaryotes are placed under the Kingdom Protista, though the boundaries of this kingdom are not well defined. What may be regarded as 'a photosynthetic protistan' by one biologist may be treated as 'a plant' by another. In this classification, Chrysophytes, Dinoflagellates, Euglenoids, Slime moulds and Protozoans are included under Protista.

Members of Protista are primarily aquatic. This kingdom forms a link with the other kingdoms dealing with plants, animals and fungi, because it stands at the boundary between them.

Being eukaryotes, the protistan cell body contains:

• a well defined nucleus
• other membrane-bound organelles …