Autotrophic:the organism prepare their own food by the process of photosynthesis. Examples- dinoflagellates, diatoms and euglenoids.
Holozoic: In this mode, the individual captures and ingest the food. Examples- Amoeba, Paramecium.
Saprotrophic: In this mode the organism releases enzymes into surroundings where the enzymes convert organic matter into simple absorbable form. Example- slime moulds.
Parasitic: some protist get their food from the body of the other organisms.The individual which obtain its food is called parasite and the organism from which parasite gets its food is called host. Example- Trypanosoma, Giardia, Entamoeba, Plasmodium.