AP BIOLOGY

Detailed explanation-1: -Protozoa are single celled organisms. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. They live in a wide variety of moist habitats including fresh water, marine environments and the soil.

Detailed explanation-2: -Abstract. Soil protozoa include naked amebae, testate amebae, flagellates, ciliates, microsporidia, and sporozoans. So far, about 1600 species have been recorded from soil, many of which have special adaptations to the soil environment.

Detailed explanation-3: -Protozoa are one-celled animals found worldwide in most habitats. Most species are free living, but all higher animals are infected with one or more species of protozoa. Infections range from asymptomatic to life threatening, depending on the species and strain of the parasite and the resistance of the host.

Detailed explanation-4: -Protozoans play important roles in the fertility of soils. By grazing on soil bacteria, they regulate bacterial populations and maintain them in a state of physiological youth-i.e., in the active growing phase. This enhances the rates at which bacteria decompose dead organic matter.

Detailed explanation-5: -Protozoa: Protozoa are unicellular animals. Some are free-living, others are parasites. Several parasitic protozoans cause diseases in human beings, domestic animals and plants. For example, Plasmodium, a protozoan, causes malaria.