Protozoa

Protozoa   Sub Kingdom: Protozoa (Belongs to kingdom Protista) Common Name: Dinoflagellates, amoebas, paramecia, plasmodium (Depends on the species) Appearance: Protozoa are single-celled, oval, or spherical eukaryotic organisms. They vary greatly in size from 1 micrometer to several millimeters due to their wide distribution around the globe. Since they are motile organisms, they may have pseudopodia, cilia, or flagella for mobility. Host Plants or Food: The mode of nutrition is strictly holozoic, which means they need pre-formed organic substances for feeding. Heterotrophic feeding means they can live off other viruses, bacteria, and fungi. Territory: Throughout the world Mode of Damage: They may either be parasitic or free-living. As parasites, they take nutrition. Habits and Life History: Protozoa are found in almost all habitats and environments, but they prefer moist environments. Since they have a single-celled structure, they can survive even in harsh conditions by forming a cyst around them. Unlike other parasites, protozoans and their hosts interact in symbiotic relationships, mutually benefiting each other. They can reproduce both sexually and asexually. However, free-living protozoa only reproduce asexually by multiplication through binary fission. The life cycle of protozoa may be divided into two parts; proliferative or trophozoite stage and resting stage. As trophozoites, they feed and actively divide, however in case of unfavorable conditions; they form a cyst around themselves for protection.