Protos—first, Zoan—animal, First animal phylum Study of protozoans called Protozoology Father of protozoology – Antony von Leeuwenhoek Term Protozoa was assigned by Goldfuss Protozoa belong to Kingdom Protista of Haeckel Single-celled, solitary or colonial, eukaryotes Important characters Size ranges from 1µ to 5000µ Aquatic – freshwater or marine forms, or endoparasites Grade of organization– protoplasmic or subcellular Locomotion by cilia, flagella or pseudopodia, or absent Skeleton – may or may not be present; if present then either calcareous or siliceous. Foraminifers have external shell of CaCO3 ( ex. Polystomella), whereas Radiolarians have internal plates of silica Osmoregulation by contractile vacuole in freshwater protozoans (isotonic to 0.8 % NaCl solution). C.V.…