introduction of phylum Protozoa

Protozoa:-

         The word Protozoa is derived from two Greek words Protos-which means first and zoon which means animal. The animal whose body is made up of single cell and can be visible only under the microscope is called protozoa. Protozoa are considered to be the first animals developed on the earth. Some of the protozoa have true nucleus (Eukaryotic nucleus) where as some has primitive nucleus (prokaryotic nucleus)