Characterstics of Protozoans
- Protozoa are microscopic animals.
- Protozoans are unicellular eukaryotic organisms and many of them are motile in nature.
- Commonly range from 10 to 52 micrometers, but can grow as large as 1 mm, and are seen easily by microscope.
- Body is naked or covered by pellicle( a thin layer supporting the cell membrane).
- The cytoplasm is differentiated into outer ectoplasm and inner endoplasm.
- Locomotry organ may be pseudopodia, cilia or flagella in different organisms.
- Nutrition may be holophytic, hollozoic,saprozoic or parasitic.
- Respiration occurs by diffusion through body surface.
- Reproduction by both:-sexual or asexual .Sexual reproduction takes place by the process of conjugation( or syngamy).
- They are found in 2 modes of life-Free Living, found in fresh and salt water and Parasitic, found as endoparasites on other animals.
- Protozoa exist throughout aqueous environments and soil, occupying a range of trophic levels.